PB95-964117
EPA/ROD/R05-95/292
February 1996
EPA Superfund
Record of Decision:
Mound Plant (USDOE), Area B,
Operable Unit 1, Miamisburg, OH
6/12/1995
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ENVIRONMENTAL RESTORATION PROGRAM
OPERABLE UNIT 1
RECORD OF DECISION
MOUND PLANT
MIAMISBURG, OHIO
June 1995
U.S. DEPARTMENT OF ENERGY
OHIO FIELD OFFICE
ENVIRONMENTAL RESTORATION PROGRAM
EG&G MOUND APPLIED TECHNOLOGIES
Final
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CONTENTS
DECLARATION 1
1. SITE NAME AND LOCATION 1
2. STATEMENT OF BASIS AND PURPOSE 1
3. ASSESSMENT OF THE SITE 1
4. DESCRIPTION OF REMEDY 1
5. STATUTORY DETERMINATION 3
6. STATE CONCURRENCE 3
DECISION SUMMARY 6
1. SITE NAME, LOCATION, AND DESCRIPTION 6
2. SITE HISTORY AND ENFORCEMENT ACTIVITIES 8
3. HIGHLIGHTS OF COMMUNITY PARTICIPATION 10
4. SCOPE AND ROLE OF OPERABLE UNIT 11
5. SITE CHARACTERISTICS 12
5.1. History of OU 1 12
5.2. Geologic Setting 15
5.3. Hydrologic Setting 15
5.4. Contaminant Occurrence 17
5.4.1. Soils 17
5.4.2. Groundwater 17
6. SUMMARY OF SITE RISKS 17
6.1. Contaminant Identification 20
6.2. Exposure Assessment ' 20
6.2.1. Exposure Setting 20
6.2.2. Characterization of Exposure Pathways 22
6.3. Toxicity Assessment 24
6.3.1. Toxicity for Noncarcinogenic Effects 24
6.3.2. Toxicity for Carcinogenic Effects 24
6.4. Risk Characterization 24
6.4.1. Carcinogenic Risk Characterization - Future Resident Farmer Scenario 24
6.4.2. Carcinogenic Risk Characterization - Future Indoor Industrial Park Worker
Scenario 28
6.4.3. Carcinogenic Risk Characterization - Future Outdoor Industrial Park Worker
Scenario 28
6.4.4. Noncarcinogenic Risk Characterization - Future Resident Farmer Scenario . . 29
6.4.5. Noncarcinogenic Risk Characterization - Future Indoor Industrial Park Worker
Scenario 29
6.4.6. Noncarcinogenic Risk Characterization - Future Outdoor Industrial Park Worker
Scenario 30
6.4.7. Risk Characterization 30
6.5. Summary 30
6.6. Additional Considerations 34
6.6.1. Ecological Risk 34
6.6.2. Immediate Points of Exposure 35
6.7. Risk Assessment for thB Selected Industrial Future Use Scenario 35
6.8. Remedial Action Objectives 37
6.8.1. Soils 37
6.8.2. Groundwater 37
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June 1995
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7. DESCRIPTION OF ALTERNATIVES 37
7.1. Common Elements 39
7.2. Description of the Alternatives 39
8. SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES 40
8.1. Threshold Criteria 41
8.1.1. Overall Protection 41
8.1.2. Compliance with ARARs 41
8.2. Balancing Criteria 41
8.2.1. Short-Term Effectiveness 44
8.2.2. Long-Term Effectiveness and Permanence 44
8.2.3. Overall Protection of Human Health and the Environment 45
8.2.4. Reduction of Mobility, Toxicity, and Volume Through Treatment 45
8.2.5. Implementabiiity 45
9. SELECTED REMEDY 46
10. STATUTORY DETERMINATIONS 47
11. DOCUMENTATION OF SIGNIFICANT CHANGES 48
RESPONSIVENESS SUMMARY 50
1. OVERVIEW 50
2. BACKGROUND ON COMMUNITY INVOLVEMENT 50
3. SUMMARY OF PUBLIC COMMENTS RECEIVED DURING PUBLIC COMMENT PERIOD AND DOE
RESPONSES 52
3.1. Summary and Response to Local Community Concerns 52
3.2. Comprehensive Response to Specific Legal and Technical Questions 59
4. REMAINING CONCERNS 59
ATTACHMENT A STATE CONCURRENCE LETTER
ATTACHMENT B ARARs TABLES
ATTACHMENT C COMMUNITY RELATIONS ACTIVITIES FOR OU 1, AREA B
FIGURES
1. Topographic features of the Mound Plant area 7
2. Mound Plant OU boundaries 9
3. OU 1 features 13
4. Location of OU 1, showing representative groundwater contours (11/02/93) and plant
production wells 16
5. Conceptual pathway model for OU 1 21
TABLES
1. Summary of COPCs 18
2. Toxicity Values - Potential Noncarcinogenic Effects 25
3. Toxicity Values - Potential Carcinogenic Effects 26
4. Slope Factors for Radionuclides of Concern at Mound Plant 27
5. Carcinogenic Risk Characterization Summary Table 31
6. Noncarcinogenic Risk Characterization Summary Table 32
7. Summary of Risk for OU 1 (Soil and Groundwater) and Contaminants with Greatest Risk
Contribution 36
8. Preliminary Remediation Goals 38
9. Summary of Remedial Action Alternative Comparison 42
10. Summary of Detailed Cost Analysis 43
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ACRONYMS
ARAR
applicable or relevant and appropriate requirements
BVA
Buried Valley aquifer
CERCLA
Comprehensive Environmental Response, Compensation, and Liability Act
COC
contaminant of concern
COPC
contaminant of potential concern
CTE
central tendency exposure
D&D
Decontamination and Decommissioning
DCA
dichloroethane
DCE
dichloroethene
DOE
U.S. Department of Energy
ECAO
Environmental Criteria and Assessment Office (EPA)
FS
feasibility study
ft
feet
HEAST
Health Effects Assessment Summary Tables
HI
hazard index
HQ
hazard quotient
IRIS
Integrated Risk Information System
MCL
maximum contaminant level
MESH
Miamisburg Environmental Safety and Health
NCP
National Contingency Plan (CERCLA)
NPDES
National Pollutant Discharge Elimination System
NPL
National Priority List (EPA)
OAC
Ohio Administrative Code
OEPA
Ohio Environmental Protection Agency
OU
operable unit
PCB
polychlorinated biphenyl
PCE
tetrachioroethene
pCi/L
picocuries per liter
PRG
preliminary remediation goal
RAPCA
Regional Air Pollution Control Authority
RfC
reference concentration
RfD
reference dose
Rl
remedial investigation
RIR
remedial investigation report
RME
reasonable maximum exposure
ROD
Record of Decision
SARA
Superfund Amendments and Reauthorization Act
SDWA
Safe Drinking Water Act
TBC
to be considered
TCA
trichloroethane
TCDD
tetrachlorodibenzo-p-dioxin
TCE
trichloroethene
USEPA
U.S. Environmental Protection Agency
UV
ultraviolet
VOC
volatile organic compound
pg/L
micrograms per liter
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June 1 995
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RECORD OF DECISION
OPERABLE UNIT 1
AREA B. MOUND PLANT. OHIO
June 1995
DECLARATION
1. SITE NAME AND LOCATION
Operable Unit 1, Area B
Mound Plant
Miamisburg, Montgomery County, Ohio
2. STATEMENT OF BASIS AND PURPOSE
This decision document presents the selected remedial action for Operable Unit (OU) 1 at Mound Plant,
Miamisburg, Montgomery County, Ohio, which is one of six distinct areas that comprise one
contiguous site as listed on the National Priorities List (NPL) (Administrative Docket Number VW-90-C-
075). This remedial action was selected in accordance with the Comprehensive Environmental
Response, Compensation, and Liability Act (CERCLA), as amended by the Superfund Amendments and
Reauthorization Act of 1986 (SARA), and to the extent practicable, the National Oil and Hazardous
Substances Pollution Contingency Plan. This decision is based on the administrative record file for this
site.
3. ASSESSMENT OF THE SITE
Actual or threatened releases of hazardous substances from this site, if not addressed by implementing
the response action selected in this Record of Decision (ROD), may present an imminent and
substantial endangerment to public health and welfare or the environment.
4. DESCRIPTION OF REMEDY
This OU remedial action is the first of several actions planned as part of the overall remedial action for
the Mound Plant Site. The function of this remedial action is to control groundwater contamination
(primarily dilute volatile organic compounds [VOCs]), to prevent migration of contamination toward the
Mound Plant production wells and to minimize exposure to potential receptors. The pathway of
concern consists of leaching of contaminants from site soils or disposed waste; entrainment in the
groundwater flow; and withdrawal by the Mound Plant production wells or by other, future wells.
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Declaration
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k
This remedial action is not the final remedial action for the Mound Plant Site, but is intended to be a
final remedial action for OU 1. The decisions regarding remedial actions for other portions of the plant
are being addressed in other OUs. These decisions will ultimately be considered in a Site-wide remedial
investigation (Rl) and feasibility study fFS), which are in progress. Additional response actions, if
warranted, are yet to be identified or planned. A decision on the final remedial action for the Site will
be made in a subsequent decision-making process.
The selected remedy for OU 1 is collection and treatment of contaminated groundwater and disposal
of treated water. The precise method for treating the contaminated water will be determined during
the remedial design phase of the project. All extracted groundwater will be treated to levels that
comply with the requirements of the Mound Plant National Pollutants Discharge Elimination System
(NPDES) Permit. This remedy was selected using the remedial evaluation criteria set forth in the
National Contingency Plan, 40 CFR Part 300.
The major components of the selected remedy include:
Installing two groundwater extraction wells within OU 1, using standard equipment and
procedures.
Treating the extracted groundwater to remove VOCs and other constituents, as required,
using cascade aeration, UV oxidation, conventional air stripping, or other suitable treatment
units.
Discharging the treated groundwater to the Great Miami River through the existing plant
NPDES outfall or a new outfall.
Following installation and operation of the groundwater extraction wells, the chemical properties and
hydraulic behavior of the groundwater system will be monitored to verify the adequacy of the remedy.
5. STATUTORY DETERMINATION
The selected remedy is protective of human health and the environment. It complies with federal and
state requirements that are legally applicable or relevant and appropriate to the remedial action and is
cost effective. This is a final action ROD.
This remedy uses permanent solutions and alternative treatment technologies to the maximum extent
practicable for this site and satisfies the statutory preference for remedies that employ treatment that
reduces toxicity, mobility, or volume as a principal element. While the remedy calls for treatment of
contaminated groundwater, treatment of soil at the site was not found to be practicable. The tact that
the source of contamination is diffuse and no substantive onsite soil hot spots exist precludes a remedy
consisting of excavation and treatment of contaminants in soil.
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June 1995
Declaration
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Because this remedy may result in hazardous substances remaining onsite above health-based levels,
a review will be conducted within 5 years after commencement of this remedial action and at 5-year
intervals thereafter to ensure that the remedy continues to adequately protect human health and the
environment.
6. STATE CONCURRENCE
The State of Ohio (Ohio Environmental Protection Agency [OEPAD concurs with the selected remedy.
The Letter of Concurrence is attached to this ROD (Attachment A).
^ rv JUN 12 1995
~ Valdas V. Adamkus, Regional Administrator, U.S. Environmental Protection Agency, Region V Date
J. Phil Haniric, Manager, Ohio Field Office, U.S. Department of Energy Date
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June 1995
Declaration
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DECISION SUMMARY
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CONTENTS
DECISION SUMMARY 6
1. SITE NAME, LOCATION, AND DESCRIPTION 6
2. SITE HISTORY AND ENFORCEMENT ACTIVITIES 8
3. HIGHLIGHTS OF COMMUNITY PARTICIPATION 10
4. SCOPE AND ROLE OF OPERABLE UNIT 11
5. SITE CHARACTERISTICS 12
5.1. History of OU 1 12
5.2. Geologic Setting 15
5.3. Hydrologic Setting 15
5.4. Contaminant Occurrence 17
5.4.1. Soils 17
5.4.2. Groundwater 17
6. SUMMARY OF SITE RISKS 17
6.1. Contaminant Identification 20
6.2. Exposure Assessment 20
6.2.1. Exposure Setting 20
6.2.2. Characterization of Exposure Pathways 22
6.3. Toxicity Assessment 24
6.3.1. Toxicity for Noncarcinogenic Effects 24
6.3.2. Toxicity for Carcinogenic Effects 24
6.4. Risk Characterization 24
6.4.1. Carcinogenic Risk Characterization - Future Resident Farmer Scenario 24
6.4.2. Carcinogenic Risk Characterization - Future Indoor Industrial Park Worker
Scenario 28
6.4.3. Carcinogenic Risk Characterization - Future Outdoor Industrial Park Worker
Scenario 28
6.4.4. Noncarcinogenic Risk Characterization - Future Resident Farmer Scenario . . 29
6.4.5. Noncarcinogenic Risk Characterization - Future Indoor Industrial Park Worker
Scenario 29
6.4.6. Noncarcinogenic Risk Characterization - Future Outdoor Industrial Park Worker
Scenario 30
6.4.7. Risk Characterization 30
6.5. Summary 30
6.6. Additional Considerations 34
6.6.1. Ecological Risk 34
6.6.2. Immediate Points of Exposure 35
6.7. Risk Assessment for the Selected Industrial Future Use Scenario 35
6.8. Remedial Action Objectives 37
6.8.1. Soils 37
6.8.2. Groundwater 37
7. DESCRIPTION OF ALTERNATIVES 37
7.1. Common Elements 39
7.2. Description of the Alternatives 39
8. SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES 40
8.1. Threshold Criteria 41
8.1.1. Overall Protection 41
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8.1.2. Compliance with ARARs 41
8.2. Balancing Criteria 41
8.2.1. Short-Term Effectiveness 44
8.2.2. Long-Term Effectiveness and Permanence 44
8.2.3. Overall Protection of Human Health and the Environment 45
8.2.4. Reduction of Mobility, Toxicity, and Volume Through Treatment 45
8.2.5. Implementability 45
9. SELECTED REMEDY 46
10. STATUTORY DETERMINATIONS 47
11. DOCUMENTATION OF SIGNIFICANT CHANGES 48
FIGURES
1. Topographic features of the Mound Plant area 7
2. Mound Plant OU boundaries 9
3. OU 1 features 13
4. Location of OU 1, showing representative groundwater contours (11/02/93) and plant
production wells 16
5. Conceptual pathway model for OU 1 21
TABLES
1. Summary of COPCs 18
2. Toxicity Values - Potential Noncarcinogenic Effects 25
3. Toxicity Values - Potential Carcinogenic Effects 26
4. Slope Factors for Radionuclides of Concern at Mound Plant 27
5. Carcinogenic Risk Characterization Summary Table 31
6. Noncarcinogenic Risk Characterization Summary Table 32
7. Summary of Risk for OU 1 (Soil and Groundwater) and Contaminants with Greatest Risk
Contribution 36
8. Preliminary Remediation Goals 38
9. Summary of Remedial Action Alternative Comparison 42
10. Summary of Detailed Cost Analysis 43
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RECORD OF DECISION
OPERABLE UNIT 1
AREA B, MOUND PLANT, OHIO
June 1995
DECISION SUMMARY
1. SITE NAME. LOCATION. AND DESCRIPTION
The U.S. Department of Energy (DOE) Mound Plant Site (Figure 1) is located within the southern city
limits of Miamisburg, in Southern Montgomery County, Ohio. The Site is approximately 10 miles
south-southwest of Dayton and 45 miles north of Cincinnati. Miamisburg is predominantly a residential
community with some supportive commercial facilities and limited industrial development. Much of
the residential, commercial, and industrial development within a 5-mile radius of the Site is
concentrated on the Great Miami River floodplain. The adjacent upland areas are used primarily for
residences and agriculture or are unused open spaces.
Mound Golf Course and Miamisburg Mound State Memorial Park, both directly east of the facility
across Mound Road, are heavily used during favorable weather. The park is the site of a 68-ft-high
ancient Indian mound, located 380 ft east of the Mound Plant boundary. Other recreational areas
within 1 mile of the facility include the Miamisburg municipal park and swimming pool (located
immediately west of Mound Plant), Harmon Athletic Field, and Library Park. These areas are used
extensively during the summer.
There are no large lakes within a 5-mile radius of the Site. Some vestiges of the old Miami-Erie Canal
lie between the Conrail Railroad and the Dayton-Cincinnati Pike west of the site. This remnant of the
old Miami-Erie Canal is designated as OU 4. The major water body in the vicinity of the Mound Plant
is the Great Miami River. It is approximately 150 to 200 ft wide in this area.
Agricultural land within a 5-mile radial area around the Site is primarily used for corn and soybean
production and for livestock grazing.
According to 1990 census figures, the population of Miamisburg is 17,834, Dayton is 182,044, and
Montgomery County is 573,809.
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Miamisburg
Central Ave
/ Dayton
-(10 miles)
Cincinnati(45 miles)
Mound Plant
Miamisburg Indian
Mound State
Memorial
SCALE IN MILES
MND,'0U1/ROD-01/4-12-95
Figure 1. Topographic features of the Mound Plant area.
EH Program, Mound Plant Operable Unit 1, Record of Decision Decision Summary
Final June 1995 Page 7
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The only historic landmark in the vicinity of Mound Plant is the Miamisburg Mound, an ancient Indian
mound located 280 ft east-southeast of Mound Plant in Miamisburg Mound State Memorial park. The
mound — a symmetrical, conical earthwork 68 ft high and 800 ft in perimeter — is one of the largest
of its type. It is believed to be the sepulcher of a chief of the Adena culture of Mound Builders who
inhabited the Ohio region as early as 800 B.C.
OU 1 also includes the three plant production wells located along the southern plant boundary. An
extended discussion of OU 1 history, including waste disposal and construction activities, is provided
in the Rl report (RIR).
The former waste disposal sites within OU 1 (the historic landfill and associated features) are
concentrated within, beneath, and immediately adjacent to the current site sanitary landfill. These
waste disposal sites are the result of a long history of dumping, burning, moving, reworking, burying,
and partially removing wastes and placing them into the engineered structure (the Site sanitary landfill).
Currently, the area bounded by the overflow pond to the north, the paved roads to the west and south,
and the bunker area to the east can be considered a single entity. It is internally heterogeneous; not
all portions are contaminated. However, subdividing the area does not increase understanding of the
transport phenomena that are occurring, nor does it facilitate developing remedial alternatives.
2. SITE HISTORY AND ENFORCEMENT ACTIVITIES
Mound Plant was established at its present location in 1948. Currently, the facility is operated by
EG&G Mound Applied Technologies for DOE as an integrated research, development, and production
facility that supports the DOE weapons and energy programs. To reconfigure and consolidate the
nuclear complex, DOE has decided to phase out the future defense mission. As a result, the Mound
Site has been designated an environmental management site and the plant is in the process of being
converted into a commercial and industrial site.
OU 1, also identified as Area B, occupies approximately 4 acres in the southwestern portion of the
Mound Plant (Figure 2). OU 1 includes a historic landfill site that was used by the Mound Plant from
1948 to 1 974. Plant waste materials that were disposed of in OU 1 included general trash and liquid
waste. Much of this waste was later relocated and encapsuled in a site sanitary landfill constructed
in 1977. An overflow pond was constructed at the same time, partially covering the historic landfill
site. After 1974, waste was no longer disposed of in OU 1. There are known releases of volatile
VOCs from OU 1 into the adjacent Buried Valley aquifer (BVA). In addition, tritium was detected in
water samples taken from wells in OU 1, although the concentration was below the drinking water
maximum contaminant level.
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J:\IX3H\KXJNDB\nf794.dgn I33V94
WM
New Property
OU 5
OU 5
OU 2
SM/PP
Hill
Legend
Note: OU 9 encompasses the cumulative Impact at all other
Oils on the ottslte environment. Including characterization
of the BVA and the plant drainage system.
OU 6 occupies small areas within the larger boundaries
depicted; these are not shown separately.
Structures
Paved roadway
Unpaved roadway
Mound Plant boundary
OU boundaries
True
North
0
l_
700
J L
Scale in Feet
Figure 2. Mound Plant OU boundaries.
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The Mound Plant Site was placed on the CERCLA NPL in 1989. The DOE signed a CERCLA Section
120 Federal Facility Agreement with the USEPA, effective October 1990. A similar tripartite agreement
was signed among the DOE, USEPA, and OEPA in 1993. The OU 1 RI/FS was conducted between
1991 and 1994 to identify the types, quantities, and locations of contaminants and to develop ways
of addressing the contamination problems.
3. HIGHLIGHTS OF COMMUNITY PARTICIPATION
The FS and Proposed Plan for OU 1 were released to the public on 1 5 November 1994. These two
documents were made available in both the Administrative Record and in an information repository
maintained in the public reading room at the Miamisburg Senior Adult Center, 305 E. Central Avenue,
Miamisburg, Ohio 45343. The notice of availability for these two documents was published in the
Dayton Daily News on 2, 7, and 21 November, 5 and 19 December 1994; and 1,15, and 25 January
1995; in the Dayton Weekly News on 11-18 November 1994; in the Miamisburg News on 2 and
30 November, 7, 14, and 28 December 1994 and 11 January 1995; and in the Dayton Suburban
News on 28 December 1994. Dayton Suburban News advertising for the FS and Proposed Plan was
available to 160,000 persons in 1 9 local communities. A public comment period was held from
15 November 1994 through 31 January 1995.
A public meeting was held on 8 December 1 994, where representatives from the DOE, EG&G, USEPA,
OEPA, Ohio Department of Health, Agency for Toxic Substances and Disease Registry, and city of
Miamisburg answered questions about problems at the site and about the remedial alternatives under
consideration. During this meeting, members of the public questioned DOE's selection of the preferred
remedy, collection, treatment, and disposal and requested additional time to review the Proposed Plan.
As a result, a 30-day extension period for public review of the Proposed Plan was requested of the
USEPA and OEPA. This extension was approved and the public review period was extended to 31
January 1995. Substantive comments were received on the Proposed Plan; a response to the
comments received during this period is included in the Responsiveness Summary, which is part of this
ROD.
This Decision Summary presents the selected remedial action for OU 1 chosen in accordance with
CERCLA, as amended by SARA and, to the extent practicable, the NCP. The Responsiveness Summary
discusses the involvement of the community during the RI/FS and remedy selection process and shows
that the public participation requirements of CERCLA Sections 113(k| (2) (B) (i-v) and 11 7 have been
met. The decision is based on the Administrative Record.
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4. SCOPE AND ROLE OF OU
Because of the magnitude and complexity of the Mound Plant RI/FS, the Site has been divided into OUs
as a means of managing the investigation. OUs 1, 2, 4, 5, 6, and 9 generally divide the Mound Plant
Site into the geographic areas shown on Figure 2. These OUs and current objectives are as follows:
Area B, OU 1, is the subject of this ROD. It occupies approximately 4 acres in the
southwestern portion of the Mound Plant. OU 1 includes a historic landfill site that was
used by the Mound Plant from 1948 to 1974. Plant waste materials that were disposed
of in OU 1 included general trash and liquid waste. Much of this waste was later relocated
and encapsuled in a site sanitary landfill constructed in 1977. An overflow pond was
constructed at the same time, partially covering the historic landfill site. After 1974, waste
was no longer disposed of in OU 1. There are known releases of VOCs from OU 1 into the
adjacent BVA. In addition, tritium has been detected in water samples taken from wells
in OU 1, although the concentration was below the drinking water maximum contaminant
level.
Main Hill, OU 2, includes potential release sites on the Mound Plant Main Hill, including
some peripheral groundwater seeps. The scope of investigation includes characterization
of the indurated bedrock and unconsolidated overburden on the Main Hill, associated soils,
and groundwater.
Miami-Erie Canal, OU 4, addresses an abandoned segment of the Miami-Erie Canal west
of Mound Plant that contains plutonium-contaminated sediments (from a 1969 waste-line
break) and tritium-contaminated soils. It is 1 mile long, and is considered to be one
potential release site.
South Property, OU 5, includes soils with known or suspected radioactive contamination,
as well as the geographical area of the SM/PP Hill, the Plant Valley, and the New Property.
The sites within OU 5 are not currently scheduled for decontamination and
decommissioning (D&D) under the D&D Program at Mound Plant. It is anticipated that, as
sites obtain funding under the D&D Program, they may be moved from OU 5 to OU 6,
described below. As with the Main Hill, investigations of the potential source terms on the
SM/PP Hill may require characterization of the bedrock and unconsolidated overburden.
D&D Program Sites, OU 6, includes potential release sites with radioactively contaminated
soils that are undergoing cleanup or are scheduled for cleanup in the near future. Because
it is already known that the contaminated soil will be cleaned up, and because the D&D
Program is an ongoing activity (under the Atomic Energy Act) that reduces potential
impacts to human health and the environment, the scope of the RI/FS for these sites is
verification of cleanup after the soil is removed. The cleanup levels are to be determined
through the CERCLA risk assessment process.
Site-wide RI/FS, OU 9, includes off-plant migration of contaminants in groundwater, soils,
surface water and sediments, air, and flora and fauna. In addition, the Site-wide RI/FS will
ensure that a comprehensive investigation is performed by compiling all data from
individual OU investigations into a comprehensive report. Data reports from specific
site-wide investigations conducted under this work plan will be initially reported in interim
reports or technical memoranda to ensure that the off-plant and regional data are available
early.
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OU 1 encompasses an historical waste disposal area (landfill) from which there have been known
releases of VOCs to the BVA, a sole-source aquifer. The cleanup remedy for OU 1 is selected from
the alternatives discussed in the FS, which is available to the public for review. The contaminated
groundwater in OU 1 is a principal threat at this site because of the possible offsite migration of the
VOC-contaminated plume and the potential for direct ingestion of contaminants through drinking water
wells. The soil contaminants in OU 1 are restricted to the area of past disposal activity with no
discernible source detected.
5. SITE CHARACTERISTICS
5.1. History of OU 1
Cut-and-fill activities and refuse and waste disposal have occurred within OU 1 from 1948 to 1974.
However, no written manifests of the waste types and quantities exist, and uniform disposal practices
were not followed.
Before 1947, OU 1 was a residential area with two or three small houses and storage buildings.
During plant construction, the area was exploited for its gravel deposits. Removal of gravel was
routine until 1977. The gravel pit, as well as the waste disposal features discussed below, are shown
in Figure 3.
The old gravel excavation and the disturbed area just north of the excavation were used for landfill,
including open burning of trash and garbage from plant operations. A burn cage, consisting of a wire
mesh structure that caught ashes from burning wood, paper, and other materials, was used. Solid
waste, mostly paper, office, and kitchen garbage, was placed in the burn cage and ignited to reduce
its volume.
In 1954, the first burial in OU 1 occurred along the southern boundary of the old gravel quarry, just
north of and parallel to the east-west road that climbs the SM/PP Hill. A backhoB was used to
excavate an irregularly shaped trench to the maximum depth possible. Residual steel and metal debris
(such as rebar and pipe), the result of a fire that consumed the Dayton Unit salvage materials on
another part of the plant (now Area 13), were progressively buried In the trench. The debris and
backfill were regraded to just below the road level.
During 1955 and possibly 1956, empty drums that had contained thorium were buried in the
southwest corner of OU 1. A shallow excavation was made, and about 2,500 55-gallon drums were
crushed and then covered with a thin layer (about 1 to 2 ft) of soil cover. The buried drums and
backfill were regraded to just below the level of the road.
ER Program, Mound Plant Operable Unit 1, Record of Decision Decision Summary
Final June 1995 Page 12
MOUNCUMlHOODSA.V/0 6(195
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I49400CT
1496500
1496000 \
NPDES
OUTFALL
002
RETENTION
BASINS
OVERFLOW
POND
Historic Landfill
Burn Cage
V
Landfill Cells
Unused Landfill
Trench
Old Gravel Pit
Old Burial
Trench
Disposal Area For
Crushed Drums
Containing
Residual Thorium
Mound Plant
Production Wells
True
North
Scale in Feet
Figure 3. OUI features.
ER Program, Mound Plan!
Final
M0UNDUM1R0DDSA.WP 6/2/35
Operable Unrt 1, Record of Decision
June 1995
Decision Summary
Page 13
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In 1969, the state of Ohio banned open burning, and Mound Plant prohibited open burning of solid and
liquid waste in OU 1. Hazardous liquid waste was collected and disposed of offsite. Solid waste was
placed in east-west-trending trenches cut by a bulldozer.
In 1977 and 1978, the overflow pond and site sanitary landfill were constructed on the site of OU 1.
The overflow pond was built to complement the low-flow retention basins, which were constructed
in 1976 on the lower reach of the plant drainage ditch. Much of the solid waste in the historic landfill
was excavated and moved to the site sanitary landfill. Generally, debris from the Dayton Unit fire in
the first trench and empty, crushed drums that had contained thorium in the second trench were not
excavated and remained under the landfill. The volume excavated was limited by the volume required
for the pond construction.
The pond was built with a natural clay-bearing compacted glacial till liner and earthen dikes. It has a
5,000,000-gallon capacity. Effluent in the overflow pond is discharged through a standpipe in the
northwest corner of the pond to the stilling basin below the low-flow retention basins. It then goes
to the Miami-Erie Canal and to the Great Miami River through NPDES Outfall 002 at a rate of
approximately 660,000 gallons per day.
The site sanitary landfill was constructed with a 4- to 5-ft-thick clay liner consisting of onsite materials
and a cap of 3 ft of clay with 2 to 5 ft of low-permeability topsoil. The clay liner was compacted to
ensure a proper seal and integrity over time. A leachate collection system was constructed using
collection drains at the top of the lower clay liner of the landfill. The drains located in the landfill allow
any landfill liquids to move into the adjacent overflow pond. Five trench drains were installed 2 to 25
ft below the landfill liner, partially in a fine gravel/sand layer and partially in a silty clay layer. These
french drains drain moisture from under the site sanitary landfill to ensure soil slope stability.
A thin {< 2-ft-thick) layer of burned trash on the west side was excavated directly beneath the landfill
site. Approximately 100,000 cubic yards of trash was moved from the overflow pond site to the
landfill. According to personal accounts, some of the trash was saturated during excavation and the
liquid flowed from the drain pipe into the pond for 6 months afterward. No known samples of this
leachate were collected. No known drainage has occurred since the initial 6-month period. The height
of the landfill was surveyed and checked for settling a year or two after construction. Although no
known written report exists, a verbal report suggests little or no settling occurred.
Currently (1995), OU 1 remains much as it did in 1978 after the overflow pond and site sanitary landfill
were constructed. The road along the north and west boundary has been paved and, in the 1980s,
a bridge was built over the overflow channel from the plant drainage ditch to the overflow pond.
ER Program, Mound Plant Operable Unit 1, Record of Decision Decision Summary
Final June 1995 Page 14
MOUNCr.MIBOCOSA.W 8(2/55
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I
Numerous monitoring wells have been installed around OU 1 as part of area environmental
investigations.
5.2. Geologic Setting
OU 1 is partially located on a buried bedrock shelf that drops off to the west, north, and south. The
surface of the bedrock is a preglacial erosional surface that is weathered, but grades rapidly into
competent material. The bedrock section subjacent to OU 1 is dominated by shale with a significant
limestone-bearing portion truncated by erosion immediately beneath the site sanitary landfill. The next
nearest (vertically) significant limestone portion Is approximately 30 ft lower in the section and does
not intersect thB bedrock interface until some distance to the west of OU 1, at or beyond the plant
boundary. The opportunity for contaminant transport from OU 1 through limestone layers does not
exist.
The bedrock is overlain by glacial outwash materials, glacial till, and artificial fill. The outwash materials
that contain the BVA thin eastward against the Buried Valley margin, which is beneath the western
edge of OU 1 adjacent to the waste disposal areas (site sanitary and historic landfills). Only the
western portion of the site sanitary landfill overlies the BVA. The eastern portion overlies the bedrock
shelf. To the north, these outwash materials extend up the Plant Valley. The portion of the BVA
immediately adjacent to OU 1 (to the west) varies from 0 to 40 ft thick and is relatively free of fine-
grained till layers within the outwash. Typical transmissivities are high (between 30,000 and
50,000 ft2/day).
5.3. Hydrologic Setting
Groundwater occurs primarily in the outwash sediments of the BVA or in its extension up the Plant
Valley. Within the valley, gradients are steep and are governed by topography and the thickness of
the unconsolidated zone; flow is west-southwest along the valley axis. In the main part of the BVA,
to the west of OU 1, gradients are nearly flat; flow is generally south, governed by the
interrelationships among recharge, river stage, and the pumping of the Mound Plant production wells.
In the immediate vicinity of OU 1, flow is governed by the plBnt production wells and is southward
toward the pumping well, Well 0076 (Figure 4). Well 0076 is the primary plant production well.
The waste materials and contaminated soils within OU 1 are partially isolated from the hydrologic
environment. Much of the surface is engineered to provide rapid runoff. The materials immediately
below the waste disposal area are dominantly fine-grained, which may inhibit the downward movement
of water and contaminants. The water table is at or below the bedrock interface in this area, so the
ER Program, Mound Plant
Final
MDUND1\M1 RODDSA.WP 6/2/95
Operable Unit 1, Record of Decision
June 1995
Decision Summary
Page 15
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03
a
/
ER Program. Mound Plant
Final
MOUND1VM1RODDSA. WP 6/2/95
Operable Unit 1, Record of Decision
June 1995
Decision Summary
Page 16
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i
unconsolidated materials are also in the vadose zone. However, during periods of high seasonal
groundwater, some waste materials or contaminated soil are exposed to circulating waters.
5.4. Contaminant Occurrence
Contaminated media at OU 1 include both soils and waste materials within the site and the
groundwater system beneath and adjacent to the site. Chemicals of potential concern (COPC) from
the Baseline Risk Assessment are identified in Table 1.
5.4.1. Soils
The only discernible pattern for all the compounds detected during the surface and subsurface soil
sampling appears directly related to activities in and around the site sanitary landfill. A single major
source of the contaminants has not been detected and is not believed to exist. Rather, it is believed
that a random pattern of dispersed contamination is the source of the compounds. While not
exceeding established regulation limits, tetrachloromethane is present at risk-based levels of concern
(see section 6.3)
5.4.2. Groundwater
The recent groundwater sampling data (June 1992 through March 1993) identified five VOCs at levels
above proposed or established regulatory limits (40 CFR 1411 in the groundwater beneath OU 1. These
VOCs are vinyl chloride (chloroethene), trichloromethane (chloroform), 1,2-c/'s-dichloroethene (DCE),
TCE, and tetrachloroethene (PCE). Only one VOC, 1,1,1-trichloroethane (TCA), shows concentrations
offsite; the pattern of occurrence suggests a source outside OU 1. The general area impacted by
VOCs is indicated in Figure 4. Two metals (chromium and nickel) were detected above primary
drinking water standards from December 1991 to March 1993. No consistent trend exists for
concentrations of metals in the area.
6. SUMMARY OF SITE RISKS
Based on analytical data collected during the Rl, a Baseline Risk Assessment was performed using site-
related contaminants. The Baseline Risk Assessment assumes no corrective action will take place and
that no site use restrictions or institutional controls, such as fencing, groundwater use restrictions, or
construction restrictions, will be imposed. The risk assessment determines actual or potential
carcinogenic risks and/or toxic effects that the contaminants at the site pose under current and future
land use assumptions. Therefore, the assessment serves as a baseline case that can be used to
ER Program, Mound Plant
Final
MOUNDt\MinODDSA.wr> C/2.95
Operable Unit 1, Record of Decision
June 1995
Decision Summary
Page 11
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Table 1. Summary of COPCs
Groundwater |
The organic COPCs for groundwater are:
1
- 1,1,1-TCA
1 20 fJg/L
- 1,2-c/s-DCE
[ 640 (J)
A/s-(2-ethylhexyl)phthalate
I 0.23 (J)
chlordane (alpha)'
; o.on
diethyl phthalate
i ' 10 IJ)
pyrene
10 (J)
- PCE
290 U#
terrachloromethane
- TCE '
; , - 160
trichloromethane
-130 IJ} -
trichlorofluoromethane
12
viny} chloride
The radioactive COPCs (that exceeded
/background levels) are:
; - actlnium-227
- 2.27 pCi/L
plutonium-238 -
0.057
piutonium-239/"24C -
li ? III \ II ;I II l;f 1 1 l;l]§l i 1: ; II IS III: 1:1 :-i 1® \
strontium-90
0.766
tritium
13,500
uranium-235 and -236
0.188
uranium 238
1.46
The following radionuclides were retained as
groundwater COPCs because they are daughter
products of the radionuclides that were found
to exceed background levels:
radium-226 ;'
2.61 pCi/L
thorium-228
thorium-230
3.B6
thorium-232
0.588 (J)
uranium-234
0.782
Soil
The organic COPCs for soils are:
- 1,2,3,4,6,7,8-HpCDF
214 pg/g
- 1,2,3,4,6,7,8-HpCDD
259
- 1,2,3,4,7,8,9-HpCDF
41.4
- 1,2,3,4,7,8-HxCDD
8.5
1,2,3,4,7,8-HxCDF
209
- 1,2,3,5,7,8-HxCDF
63.2
- 1,2,3,6,7,8-HxCDD
28.3
- 1,2,3,7,8,9-HxCDD
39.7
- 1,2,3,7,8-PeCDF
43.2
- 2,3,4,6,7,8-HxCDF
64.1
2,3,4,7,8-PeCDF
150
- 2,3,7,8-TCOD
22.5
"" " 2,3,7,8-TCDF
132
ER Program, Mound Plant
Final
MO.If.DlWItNDDDSP WP 6/2/95
Operable Unit 1, Record of Decision
June 1995
Decision Summary
Page 1 8
-------
Table 1. (page 2 of 2)
Soil (Continued)
- OCDD
2110
- OCDF
163
1,2-DCE
6,700 /;g/kg
4-methyphenol
290
aroclor-1248
220,000
benzo(a)anthracene
3,400
benzo(e)pyrBne
2,500
trenzotojfluoranthene
4,000
benzol k)fluoranthene
""" 1,500
benzoic acid
1,700
/>/s(2-ethylhexyl|phthalate
5,600
vinyl chloride
190
chrysene
2,600
dichloromethane
81
fluoranthene
8,300
indeno(1,2,3-cd)pyrene
1,200
phenol
120 (J)
pyrene
7,200 (J)
- PCE
24,000
toluene
7,100
- TCE
970 (J)
Inorganic COPCs consist of:
fluoride
1 2.6 mg/kg
| - nitrate
16.87
silver
6.3
The radioactive COPCs (that exceeded
background levels) are:
plutonium-238
17.9 pCk'g
plutonium-2 39/240
1.2
strontium-90
5.76
tritium
40.3
The following radionuclides were retained as
soil COPCs because they are daughter products
of the radionuclides that were found to exceed
background levels:
thorium-228
1.3 pCi/G
thorium-232
1.04
uranium-235/236
0.091 (J)
COPC - contaminants of potential concern
pCi/g - picocuries per gram
DCE - dichloroethene
pCi/L - picocuries per liter
(J) - estimated quantity
pg/g - picogram per gram
mg/kg - milligram per kilogram
TCA - trichloroethane
/;g/kg - microgram per kilogram
TCE - trichloroethene
PCE - tetrachloroethene
- contaminant contributing significant; risk
ER Program, Mound Plant Operable Unit 1, Record of Decision Decision Summary
Final June 1995 Page 19
MOJND1W1RODOSF.WP 6/2.95
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L
compare the relative effectiveness of alternative remedial strategies in reducing public health risks.
This Baseline Risk Assessment focuses on exposure of hypothetical future workers or residents to soil
and groundwater contamination.
The Baseline Risk Assessment estimates risk associated with potential pathways identified by the
conceptual site model presented in Figure 5. It also identifies pathways that exceed acceptable risk,
so that the remediation process is focused on pathways that present a threat to human health and the
environment.
6.1. Contaminant Identification
The levels of contamination found in the different media at the Site are reported in the RIR.
Identification of contaminants of potential concern (COPCs) is presented in Section 5 of the RIR. The
COPCs were listed in Table 1. As discussed in section 6.4 below, the list of COPCs was reduced to
only those contaminants that contribute significantly to the risk. These are highlighted in Table 1.
6.2. Exposure Assessment
The objective of the exposure assessment is to estimate the type and magnitude of exposures to
COPCs that are present at or migrating from Area B. The exposure pathway is the mechanism by
which an individual or population is exposed to chemicals at or originating from a site. Each exposure
pathway requires a source or release from a source, an exposure point, and an exposure route.
6.2.1. Exposure Setting
The exposure setting, which includes Area B climate, vegetation, groundwater hydrology, and other
characteristics, is described in detail in the RIR. The nearest populations are less than 750 ft west of
OU 1, within the city of Miamisburg. The 1 990 census gives the population of Miamisburg as 1 7,834,
Dayton as 182,044, and Montgomery County as 573,809. Miamisburg is predominately a residential
community, with some supportive commercial facilities and limited industrial and agricultural
development.
Most of the residential, commercial, and industrial development within a 5-mile radius of the site is
concentrated on the Great Miami River floodplain. The adjacent upland areas are used primarily for
residences and agriculture or are unused open spaces. Agricultural land within a 5-mile radius of the
site is primarily used for corn and soybean production and livestock grazing.
ER Program, Mound Plant Operable Unit 1, Record of Decision Decision Summary
Final June 1995 Page 20
M0UN31\M 1RODDSA WP 6'2,95
t
-------
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Primary
Source
Primary
Release
Mechanism
Secondary
Source
Secondary
Release
Mechanism
Pathway
Exposure
Route
Receptor
Drums, tanks,
waste lines
Spills/leaks
Landfills,
burial sites,
old cave
Leaching
Retention
basins/
wastewater
treatment
system
Gas/vapor
transport
Infiltration
Overflow
Dust
Alr°
MI Inhalation
Infiltration
Groundwater
Ingestion
Food source*
Inhalation
Dermal contact
Surface
Runoff
>
Soil/
-ik
Runoff
Surface Water/
disposed
w
Sediment
W
Sediments9
i
Operations
Historical "
stack
emissions
Soil
i—~
w
Ingestion
Food source
Dermal contact
Direct radiation
h>
Ingestion
Food source1
Dermal contact
Direct radiation
LEGEND
a ECOLOGICAL RISK assessment to be
conducted in OU 9.
b FUTURE WORKER - Works outside or within a
building on the site as a laborer. Receptor is
exposed to contaminants in environmental media;
not an evaluation of occupational exposure.
c FUTURE RESIDENT - Uses groundwater
onsite.
d TERRESTRIAL BIOTA - Analysis of terrestrial
biota will include quantitative analysis to the
extent possible, but will not be possible for all
exposure routes, such as dermal contact.
e FOOD INGESTION from the groundwater
pathway will be based on consumption of
vegetables grown in gardens irrigated with
contaminated groundwater.
f FOOD INGESTION from the soli pathway will
include ingestion of plants that have taken up
contaminants from soil.
g INVESTIGATION to be conducted in OU 9
NOTE: Shaded areas Indicate aspects relevant to Area B Feasibility Study
Possible intersection of pathway and receptor.
Because there are two groundwater receptors
being used (future worker and future resident),
the higher of the two risk calculations will be
used in the assessment.
Figure 5. Conceptual pathway model for OU 1.
MND/OU1/ROD-02/4-10-95
-------
The major water body in the vicinity of OU 1 is the Great Miami River. It is approximately 150 to 200
ft wide in this area. The river is used for pleasure boating and sport fishing, primarily during the
summer. Swimming is not permitted in the river.
6.2.2. Characterization of Exposure Pathways
OU 1 is located within a government-owned and restricted facility. Unrestricted access and
development of the site is possible only if DOE releases the property. No one presently lives on or
otherwise uses the property; current workers do not work on a continual basis within Area B.
Three OU 1 production wells supply or have supplied water to the Mound Plant. One well, production
well 0071, is no longer in use because volatile organic contaminants were detected at concentrations
exceeding USEPA maximum contaminant levels (MCLs) and Ohio drinking water standards. The other
two wells, production wells 0076 and 0271, are still in use and have organic concentrations below
EPA MCLs and Ohio drinking water standards. Since Mound Plant is taking water from OU 1 that
meets acceptable drinking water standards, a current worker scenario was not considered for the
Baseline Risk Assessment.
The Baseline Risk Assessment involves 1) the determination of contaminant concentrations at exposure
points for a future resident farmer scenario and future indoor and outdoor industrial park worker
scenarios, and 2) the estimation of contaminant intake through potential exposure pathways.
Two Types of exposures were evaluated for the future farmer resident scenario. These exposure types
are denoted as the reasonable maximum exposure (RME) and the central tendency exposure (CTE).
The RME is defined as a "reasonable worst case" that is conservatively high, yet still has a reasonable
likelihood of occurring. Key features of an RME are that one would expect at least 90 percent of
actual exposures to be lower and that it could occur. The CTE, on the other hand, is an "average
case." Fifty percent of actual exposures are expected to be lower or higher than the CTE. High
exposures will typically fall between the CTE and the RME.
The exposure scenario for the future farmer resident includes all potential pathways identified in the
site conceptual model that could lead to quantifiable exposure. The farmer is assumed to be exposed
through the following routes:
Ingestion of groundwater.
Incidental ingestion of and dermal contact with surface water while swimming.
ER Program, Mound Plant
Final
MO'JNDINMinODQSA WF 6'2/95
Operable Unit Record of Decision
June 1995
Decision Summary
Page 22
i
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Dermal contact and inhalation of VOCs while showering with groundwater.
Inhalation of resuspended dust while plowing/cultivating crops and garden produce and
under usual dust resuspension conditions.
Incidental ingestion of soil.
External exposure to radiation emitted from radionuclides in soil.
Dermal contact with chemicals in soil.
Ingestion of homegrown produce grown in contaminated soil.
Ingestion of livestock that have ingested contaminated soil and contaminated plants.
It is assumed that the future onsite industrial park worker will work within the Area B location for 25
years (RME). For the CTE, it is assumed that the worker will be employed on the site for 9 years
(assumed equal to residential). As with the future farmer resident, the source of water for the
industrial park comes from contaminated onsite wells that workers use for showering at the end of the
workday.
In the future indoor industrial worker scenario, it is assumed that the worker performs job duties within
a structure or building for 8 hours a day, 250 days a year. The indoor worker is assumed to be
exposed through the following routes:
Ingestion of groundwater.
Inhalation of indoor vapors.
Inhalation of indoor particulates.
Inhalation of VOCs while showering with groundwater.
Dermal contact with contaminants while showering with groundwater.
For the future outdoor industrial worker scenario, the following exposure routes were evaluated:
Ingestion of groundwater.
Inhalation of outdoor particulates and vapors.
Ingestion of soil.
Dermal contact with chemicals in soil.
Inhalation of VOCs while showering with groundwater.
Dermal contact with chemicals while showering with groundwater.
ER Program, Mound Plan!
Final
V.OUNDIXMIRC/DDSA.WP 6/2/95
Operable Unit 1, Record of Decision
June 1995
Decision Summary
Page 23
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6.3. Toxicity Assessment
The purposes of the toxicity assessment are to weigh available evidence regarding the potential for
particular contaminants to cause adverse effects in exposed individuals and to provide an estimate of
the relationship between the extent of exposure to a contaminant and the increased likelihood and/or
severity of adverse effects. This includes the preparation of fate and toxicity profiles for each of the
chemicals and identification of human health criteria. The sources of toxicity data include the
Integrated Risk Information System (IRIS), the Health Effects Assessment Summary Tables (HEAST),
the USEPA Environmental Criteria and Assessment Office (ECAO), and USEPA Region III.
6.3.1. Toxicity for Noncarcinoqenic Effects
The USEPA Office of Research and Development has calculated acceptable intake values, denoted as
reference doses (RfDs) or reference concentrations (RfCs), for long-term (chronic) exposure to
noncarcinogens. The most recent oral RfDs and inhalation RfCs of the COCs and the associated
sources are summarized in Table 2.
6.3.2. Toxicity for Carcinogenic Effects
For chemical carcinogens, the EPA Office of Research and Development has calculated estimates of
the carcinogenic potential. These estimates, or slope factors, correlate intake of a carcinogen with an
increased risk of cancer. The most recent oral and inhalation slope factors from IRIS, HEAST, USEPA,
and ECAO, along with evidence and slope factor sources for COCs, are summarized in Table 3.
The USEPA currently classifies all radionuclides as Group A, known human carcinogens. The ingestion,
inhalation, and ground exposure slope factors for the various radionuclides of concern at Mound Plant
are summarized in Table 4.
6.4. Risk Characterization
In this section, toxicity and exposure assessment are summarized and integrated into quantitative
expressions of risk. Both noncarcinogenic and carcinogenic effects are evaluated.
6.4.1. Carcinogenic Risk Characterization - Future Resident Farmer Scenario
For potential carcinogenic risks, the probability that an individual will develop cancer over a lifetime
of exposure is estimated from daily intakes and dose response information (carcinogen potency
ER Program, Mound Plant Operable Unit 1, Record of Decision Decision Summary
Final Jur»e 1995 Page 24
MOt/NDIiMlROC^SA.V.P 6/2/95
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S -n m
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Table 2. Toxicity Values - Potential Noncarcinogenic Effects
Chemical
Chronic Inhalation RfC
(mg/m3)
RfC Source
Chronic Ingestion RfD
(mg/kg/day)
RfD Source
Organic Chemicals
1,2-c/s-Dichloroethene
--
--
1.0E-02
HEAST
1,2-Dichloroethane
1.0E-02
ECAO
-
-
2,3,7,8-TCDD (Dioxins)
--
--
--
--
Archlor-1 248 (PCB)
--
--
--
--
Benzo(a)pyrene
-
--
--
--
Chlordane (alpha)
--
--
6.0E-05
IRIS
Tetrachloroethene (PCE)
-
--
1.0E-02
IRIS
T etrachloromethane
2.0E-03
ECAO
7.0E-04
IRIS
Trichloroethene
--
--
6.0E-03
ECAO
Trichlormethane
--
-
1.0E-02
IRIS
Vinyl chloride
--
--
--
--
c
3
33
CD o
CO O
o_
o
ECAO - USEPA Environmental Criteria and Assessment Office
IRIS - Integrated Risk Information System
HEAST - Health Effects Assessment Summary Tables
mg/kg/day - milligrams per kilogram per day
mg/m3 - milligrams per cubic meter
RfC - reference concentration
RfD - reference dose
O
re
o
R'
o'
D
(/)
C
0)
(O
3
Cl <
-------
Table 3. Toxicity Values - Potential Carcinogenic Effects
Chemical
USEPA Weight of
Evidence"
Inhalation Slope Factor
(1 ///g/m3)
Inhalation Slope
Factor Source
Ingestion Slope Factor
(1 /mg/kg/day)
Ingestion Slope
Factor Source
Organic Chemicals
1,2-c/s-Dichloroethene
D
--
--
--
-
1,2-Dichloroethane
B2
2.6E-05
IRIS
9.1E-02
IRIS
2,3,7,8-TCDD (Dioxins)
B2
3.3E-11
HEAST
1.5E + 05
HEAST
Aroclor-1248 (PCB)
B2
--
--
7.7E + 00
IRIS
Benzo(a)pyrene
B2
1.7E-03
HEAST
7.3E + 00
IRIS
Chlordane (alpha)
B2
3.7E-04
IRIS
1.3E + 00
IRIS
Tetrachloroethene (PCE)
NA
5.8E-07
ECAO
5.2E-02
ECAO
T etrachloromethane
B2
1.5E-05
IRIS
1.3E-01
IRIS
Trichloroethene
NA
1.7E-06
ECAO
1.1E-02
ECAO
Trichloromethane
B2
2.3E-05
IRIS
6.1E-03
IRIS
Vinyl chloride
A
8.4E-05
HEAST
1.9E + 00
HEAST
aKey:
A = Known human carcinogen
B1 = Probable human carcinogen, limited human data
B2 = Probable human carcinogen, inadequate or no human data
C = Possible human carcinogen
D = Not classifiable as human carcinogen
E = Evidence that not carcinogenic in humans
ECAO - USEPA Environmental Criteria and Assessment Office
HEAST - Health Effects Assessment Summary Tables
IRIS - Integrated Risk Information System
//g/m3 - micrograms per cubic meter
mg/kg/day - milligrams per kilogram per day
NA - Weight of evidence information not available
USEPA - U.S. Environmental Protection Agency
-------
Table 4. Slope Factors for Radionuclides of Concern at Mound Plant
Ingestion
Ground Surface
Radionuclide"
(Risk/pCil
Inhalation (Risk/pCi)
IRisk/year per pCi/g)
Actinium-227 + D
3.5E-10
8.8E-08
8.5E-07
Plutonium-238
2.2E-10
3.9E-08
2.8E-11
Plutonium-239
2.3E-10
3.8E-08
1.7E-11
Plutonium-240
2.3E-10
3.8E-08
2.7E-11
Radium-226 + D
1.2E-10
3.0E-09
6.0E-06
Strontium-90 + D
3.6E-11
6.2E-11
0.0E + 00
Tritium
5.4E-14
7.8E-14
0.0E + 00
aAII radionuclides have an A (known human carcinogen) weight of evidence classification.
D - daughter
pCi - picocuries
pCi/g - picocuries per gram
ER Program, Mound Plant
Final
MOUND11M1RODDS5 WP 6" 2/95
Operable Unit 1, Record of Decision
June 1995
Decision Summary
Page 27
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factors). Carcinogenic risk depends on three factors: the dose, the carcinogenic potency of the
chemical or radionuclide, and the exposure duration. To calculate carcinogenic risk, the products of
the individual chemical exposures and carcinogenic slope factors were summed to provide the
estimated risk to the future resident.
Future resident farmer RME carcinogenic risks to the child and adult from all chemicals, radionuclides,
and pathways are 2 excess cancers per 10,000 persons exposed and 5 excess cancers per 10,000
persons exposed, respectively. The overall CTE carcinogenic risks to the child Bnd adult are 4 excess
cancers per 100,000 persons exposed and 1 excess cancer per 1 0,000 persons exposed, respectively.
For the future resident farmer scenario, the ingestion Bnd inhalation pathways contribute more than
80 percent of the carcinogenic risk. The remainder of the carcinogenic risk is attributable to dermal
contact. The overall carcinogenic risk due to external radiation exposure is less than 1x10'7.
The overall carcinogenic risks posed by groundwater are 6x10"4 and IxlO"4 for the RME and CTE,
respectively. The overall risks (RME and CTE) posed by soil COPCs are more than one order of
magnitude less than those for groundwater.
6.4.2. Carcinogenic Risk Characterization - Future Indoor Industrial Park Worker Scenario
For the future onsite indoor worker, the overall RME and CTE risks were found to be 2x10"4 and
5x1 0"5, respectively (does not include daughter product radionuclides). PCE had the highest RME risk
of 8x10'5. Groundwater COPCs contribute virtually all of the carcinogenic risk (greater than 99
percent). The soil RME and CTE risk levels are less than the lowerbound value of the USEPA target
risk range.
6.4.3. Carcinogenic Risk Characterization - Future Outdoor Industrial Park Worker Scenario
For the future onsite outdoor worker, the overall RME and CTE risks were found to be 1x10'4 and
2x105, respectively (does not include daughter product radionuclides). The ingestion and dermal
contact pathways contribute approximately 83 percent of the carcinogenic risk. PCE had the highest
RME risk of 7x10"5. Groundwater COPCs contribute the majority (approximately 95 percent) of the
overall RME Bnd CTE carcinogenic risks.
ER Program, Mound Plant
Final
VOUNOViM 1 POODSA.W® 6/2 95
Operable Unit 1, Record of Decision
June 1995
Decision Summary
Page 28
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6.4.4. Noncarcinogenic Risk Characterization - Future Resident Farmer Scenario
Noncarcinogenic risk was evaluated by calculating the hazard quotient (HQ), which is the ratio of the
estimated daily exposure of each contaminant, to the applicable chronic RfC or RfD for that
contaminant. The HQs were then summed to derive a hazard index (HI) for each exposure route and
for all exposures combined. All RME and CTE noncarcinogenic HQs and His from all pathways are
presented in the RIR.
An HI of greater than 1.0 at any time during an individual's lifetime indicates that there may be a
potential for noncarcinogenic effects. The overall RME His for the child and adult in the future farmer
scenario are 21 and 18, respectively. For the future farmer CTE, the overall His are 12 for the child
and 11 for the adult.
For the future farmer scenario, the inhalation pathway contributes to approximately 80 percent of the
overall noncarcinogenic risk. Tetrachloromethane, TCE, and PCE were the only COPCs with overall
RME His exceeding unity. These COPCs contributed to approximately 90 percent of the overall
noncarcinogenic risk. Tetrachloromethane had the highest overall RME and CTE HI of 31 and 20,
respectively.
Groundwater COPCs contribute virtually all of the noncarcinogenic risk (greater than 99 percent). The
soil RME and CTE His are two orders of magnitude less than unity.
6.4.5. Noncarcinogenic Risk Characterlration - Future Indoor Industrial Park Worker Scenario
For the future indoor industrial park worker scenario, the overall RME and CTE His were 17 and 11,
respectively. The inhalation pathway contributes approximately 96 percent of the overall
noncarcinogenic risk. Tetrachloromethane had the highest RME and.CTE His of approximately 15 and
1 0, respectively.
Tetrachloromethane was the only COPC with RME and CTE His that exceeded unity. The overall RME
and CTE His, with the exception of tetrachloromethane, were found to be below unity. The
groundwater COPC His contributed almost 100 percent of the noncarcinogenic risk. The soil COPC
His were approximately 10 orders of magnitude less than unity.
ER Program, Mound Plant Operable Unit 1. Record of Decision Decision Summary
Final June 1995 Page 29
MOUNH> W* HODDSA WF S'2/95 '
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6.4.6. Noncarcinoqanic Risk Characterization • Future Outdoor Industrial Park Worker Scenario
For the future outdoor industrial park worker scenario, the overall RME and CTE His were 15 and 9,
respectively. The inhalation pathway contributes approximately 95 percent of the overall
noncarcinogenic risk. Tetrachloromethane had the highest RME and CTE His of approximately 14 and
9, respectively.
Tetrachloromethane was the only COPC with RME and CTE His that exceeded unity. The overall RME
and CTE His, with the exception of tetrachloromethane, were found to be below unity.
The groundwater COPC His contributed almost 100 percent of the noncarcinogenic risk. The soil
COPC His were approximately three to four orders of magnitude less than unity.
6.4.7. Risk Characterization
Tables 5 and 6 present the range of potential carcinogenic and noncarcinogenic risks associated with
Area B, respectively. The lowerbound values represent CTE values, while the upperbound values
represent RME values. These ranges indicate the uncertainties associated with Area B risks and
provide information on the sensitivity of each exposure scenario to the values of its numerical
parameters.
6.5. Summary
The risk assessment performed for OU 1, Area B, has provided estimates of potential relative risk for
the future farmer resident and for future worker exposure to groundwater and soils. The scenarios that
were developed are conservative and hypothetical; relative risks determined for these can be
interpreted more accurately by considering the assumptions in the calculations.
For the future farmer resident, the total RME carcinogenic risks to the child and adult from all
chemicals, radionuclides, and pathways are 2 and 5 excess cancers in 10,000 persons exposed,
respectively. The combined overall RME adult and child risk may be of potential concern because it
lies outside the upperbound value of the EPA target carcinogenic risk range of 1x106to 1x10"4. The
majority of the carcinogenic risk comes from PCE and trichloromethane.
Radium-226 and thorium-228 were the only daughter product radionuclides with RME carcinogenic
risks that exceed 1x10 s for the future farmer resident. The RME carcinogenic risk for thorium-228
was found to be IxlO"4 in soil, which is higher than the risks for all other chemicals and radionuclides
ER Program, Mound Plant Operable Unit 1, Record of Decision Decision Summary
Final June 1 995 Page 30
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Table 5. Carcinogenic Risk Characterization Summary Table
Carcinogenic Risk Range ILowerbound Value
Value = RME|
= CTE, Upperbound
Chemical
Future Farmer
Resident (Adult +
Child)
Future Indoor
Industrial Park Worker
Future Outdoor
Industrial Park
Worker
Organic Chemicals
1,2-Dichloroethane
8E-07 - 3E-06
3E-07 - 2E-06
7E-08 - 4E-07
2,3,7,8-TCDD (Dioxins)
2E-06 - 8E-06
4E-22 - 2E-21
3E-07 - 2E-06
Aroclor-1248 (PCB)
7E-07 - 5E-06
9E-08 - BE-07
Benzo(a)pyrene
2E-06 - 1E-05
3E-10 - 1E-09
2E-07 - 2E-06
Chlordane (alpha)
3E-06 - 2E-05
9E-07 - 4E-06
4E-07 - 2E-06
JTetrachloroethene
6E-05 - 3E-04
2E-05 - 8E-05
1 E-05 - 7E-05
Tetrachloromethane
5E-06 - 2E-05
2E-06 - 8E-06
6E-07 - 3E-06
Trichloroethene
9E-06 - 4E-05
4E-06 - 2E-05
1E-06 - 5E-06
Trichloromethane
4E-05 - 1 E-04
2E-05 - 7E-05
2E-06 - 1 E-05
Vinyl chloride
2E-05 - 8E-05
6E-06 - 3E-05
2E-06 - 1 E-05
Radionuclides
Actinium-227
3E-06 - 2E-05
9E-07 - 5E-06
9E-07 - 5E-06
Plutonium-238
2E-06 - 7E-06
5E-07 - 2E-06
5E-07 - 2E-06
Plutonium-239/240
2E-06 - 1 E-05
7E-07 - 4E-06
7E-07 - 4E-06
Strontium-90
2E-06 - 1 E-05
4E-08 - 2E-07
4E-08 - 2E-07
Tritium
2E-06 - 1 E-05
5E-07 - 3E-06
5E-07 - 3E-06
CTE - central tendency exposure
RME - reasonable maximum exposure
TCDD - tetrachlorodibenzo-p-dioxin
ER Program, Mound Plant
Final
M0UN31W1 RODDS5.WP 6.'195
Operable Unit 1, Record of Decision
June 1995
Decision Summary
Page 31
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Table G. Noncarcinogenic Risk Characterization Summary Table
Chemical
Noncarcinogenic Hazard Index Range (Lowerbound Value = CTE,
Upperbound Value = RME)
Future Farmer
Resident lAdult +
Child)
Future Indoor
Industrial Park Worker
Future Outdoor
Industrial Park Worker
Organic Chemicals
1,2-CAS-Dichloroethene
5.3E-01 - 1.1E + 00
5.5E-02 - 1.0E-01
5.5E-02 - 1.0E-01
1,2-Dichloroethane
5.2E-01 - 8.2E-01
2.6E-01 - 4.1E-01
2.2E-01 - 3.7E-01
Chlordane (alpha)
2.3E-01 - 1.4E + 00
3.7E-02 - 5.7E-02
3.7E-02 - 5.7E-02
Tetrachloroethene
1.4E + 00 - 3.0E + 00
2.1E-01 - 3.5E-01
2.1E-01 - 3.5E-01
T etrachloromethane
2.0E + 01 - 3.1E+01
9.9E + 00 - 1.5E + 01
8.6E + 00 - 1.4E + 01
Trichloroethene
5.6E-01 - 1.1E + 00
6.8E-02 - 1.2E-01
6.8E-02 - 1.2E-01
Trichloromethane
1.2E-01 - 2.4E-01
1.3E-02 - 2.5E-02
1.3E-02 - 2.5E-02
CTE - central tendency exposure
RME - reasonable maximum exposure
ER Program, Mound Plant
Final
M0UND1 RODDSF.WP 00,02/95
Operable Unit 1, Record of Decision
June 1995
Decision Summary
Page 32
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detected in soil. However, thorium-228 was detected at concentration levels equivalent to
background.
His that exceed unity indicate that the chemical may cause adverse health effects to exposed
individuals. As a rule, the greater a chemical HI exceeds unity, the greater the level of potential
concern. For the future onsite resident scenario, tetrachloromethane and PCE pose the most significant
noncarcinogenic risks, with overall RME His 3 to 31 times greater than unity. Since the sum of all
COPC RME and CTE His are 24 to 39 times greater than unity, exposure to all COPCs could produce
adverse health effects for the potential future residential farmer.
For the future indoor industrial park worker, the overall probability of cancer occurrence was 2 excess
cancers in 10,000 persons exposed (RME) and 5 excess cancers in 100,000 persons exposed (CTE).
PCE, chlordane (alpha), 1,2-dichloroethane, tetrachloromethane, trichloromethane, vinyl chloride, TCE,
actinium-227, plutonium-238, plutonium-239/240, and tritium had RME risk levels exceeding IxlO6.
The majority of carcinogenic risk contribution is from PCE and trichloromethane. The overall indoor
worker RME risk may be of potential concern because it exceeds the US EPA target risk range of IxlO"6
to 1x10".
For the future outdoor industrial park worker, the overall probability of cancer occurrence was 1 excess
cancer in 10,000 persons exposed (RME) and 2 excess cancers in 100,000 persons exposed (CTE).
PCE contributes more than half of the carcinogenic risk. The overall outdoor worker RME risk may be
of potential concern because it lies at the upperbound limit of the USEPA target risk range.
Thorium-228 was the only daughter product radionuclide with RME and CTE carcinogenic risks that
exceeded 1x10'6 for both the future indoor and outdoor workers. The future indoor and outdoor
worker RME carcinogenic risks for thorium-228 were both found to be 2x10"5 in soil; these risk levels
are significantly higher than the risks for all other chemicals arTd radionuclides detected in soil.
However, thorium-228 was detected at concentration levels equivalent to background.
Tetrachloromethane is the only COPC that had RME and CTE His exceeding unity for both the future
indoor and outdoor industrial park worker scenarios. Without tetrachloromethane, the overall RME and
CTE His are approximately equal to or less than unity for the future indoor and outdoor workers.
The risks to future indoor and outdoor workers are based on chemical and radionuclide concentrations
in groundwater and soil within and directly adjacent to the sanitary landfill in Area B. The future
worker scenarios assume that exposures take place within Area B and that the drinking and domestic
water supply is exclusively from Area B.
ER Program; Mound Plant Operable Unit 1, Record of Decision Decision Summery
Final June 1995 Page 33
VOU>JC>1\M1fOODSA.WP 6/2,'95
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The contaminants of concern (COCs) that are the focus of remedial action efforts are defined as
COPCs with either risks that exceed the minimum acceptable levels or risks that provide a significant
contribution to the overall risk in any one of the exposure scenarios. A COPC provides a significant
contribution to the overall risk if its hazard index exceeds 0.1 or its carcinogenic risk exceeds 1x10"6.
Based on these criteria, the COCs delineated by the OU 1, Area B, risk assessment for the resident
scenario are the following:
For groundwater:
- 1,2-Dichloroethane.
- 1,2-c/s-DCE.
- Benzo{b)fIuoranthene.
- Chlordane (alpha).
- PCE.
- Tetrachloromethane.
- TCE.
- Trichloromethane.
- Vinyl chloride.
- Actinium-227.
- Plutonium-238.
- Piutonium-239/240.
- Radium-226.
- Tritium.
For soil:
- 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) (dioxins).
- Aroclor-1248 polychlorinated biphenyl (PCB).
- Benzo(a)pyrene.
- Plutonium-238.
- Strontium-90.
6.6. Additional Considerations
6.6.1. Ecological Risk
An evaluation of the potential ecological impacts of OU 1 was not conducted. The ecological risk
assessment will be performed on a site-wide basis during the OU 9 Site-Wide Rl. The Mound Plant
ecological risk assessment will be performed in conjunction with the site-wide ecological assessment.
The site-wide ecological risk assessment will be based on data collected as part of the OU 9 Rl, along
with the information obtained from the site-wide ecological assessment and other studies that have
evaluated ecological conditions around the Mound Plant facility. The issue of ecological impacts will
be addressed in the final determination for the site as a whole.
ER Program, Mound Plant
Final
M0UND1vM*q0DDSVWP 6/2/95
Operable Unit 1, Record of Decision
June 1995
Decision Summary
Page 34
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6.6.2. Immediate Points of Exposure
The most immediate point of exposure for contaminants originating in OU 1 also lies within the
confines of OU 1 —the system of plant production wells. Production well 1 was taken offline due to
increasing levels of VOCs in the discharge water. Production well 3 is now the primary source of
process and potable water for the plant. Production well 2 is pumped as required to provide a
supplemental source of plant water.
6.7. Risk Assessment for the Selected Industrial Future Use Scenario
The preceding sections discussed the Baseline Risk Assessment—that is, a measure of the risks posed
by the site if no remediation took place. To select a remedy, a realistic future use scenario was
determined to help define cleanup goals. It has been agreed among the USEPA, OEPA, and DOE that
the appropriate land use for OU 1 is industrial. Offsite, the appropriate land use remains residential.
Thus, the context for onsite soil remediation is that of an industrial park, with no onsite groundwater
use or standards. By the same token, the offsite contamination (limited to the groundwater pathway)
must be protected to residential use standards. The point of compliance is established outside the
roadways that bound the former waste disposal areas to the south and west. The assessment of risk
expected under this future use scenario is discussed below.
The risk assessment for OU 1 addressed future public health risks, defining the performance
requirements that remedial actions would meBt. The conceptual pathway model is shown in Figure 5.
This risk assessment focused on the exposure of hypothetical future site workers to soil contamination
through inhalation, incidental ingestion, external exposure to radiation emitted from radionuclides in
soil, or dermal contact with the soil by an onsite industrial worker.
The results of the risk assessment of the future outdoor worker show that two of the COPCs were
found to have RME lifetime excess cancer-risks above 1x10 6. 2,3,7,8-TCDD and benzo(a|pyrene each
had an estimated excess cancer risk of 2x10"®. The combined carcinogenic risk is 4x10"6. Because
the NCP specifies a target cancer risk range of 1x10 4 to 1x10"6, and because this risk is already near
the lower end of this range, the soil pathway does not need further consideration. For noncarcinogens,
the HI was less than one for soil, indicating that noncarcinogenic health effects are not of concern.
The risk assessment also evaluated risks associated with future potential offsite residential use of
groundwater. The risks could result from direct exposure to contaminants by groundwater ingestion,
ingestion of groundwater-irrigated produce, and dermal contact and inhalation of VOCs while
showering with groundwater. The analysis dealt with all the COCs. Results of the analysis are shown
in Table 7.
ER Program, Mound Plant
Final
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Operable Unit 1, Record of Decision
June 1995
Decision Summary
Page 35
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Table 7. Summary of Risk for OU 1 (Soil and Groundwater) and Contaminants with Greatest Risk Contribution
Overall Risk
Percent of
Exposure Due to
Ingestion and
Inhalation
Percent of Risk
via Groundwater
Pathways
COC with
Greatest Effect
COC Effect
RME
CTE
RME
CTE
Carcinogenic Risk
Resident Farmer or
Resident3
Adult
Child
5 x 10'4
1 x 10'4
1 x 104
3 x 10 5
83
96
T etrachloroethene
Trichloromethane
2 x 104
(Adult + Child)
1 x 10'4
(Adult + Child)
6 x 10 5
(Adult + Child)
4 x 10'5
(Adult + Child)
Industrial Worker
(Indoor)
2 x 104
5 x 105
80
100
T etrachloroethene
Trichloromethane
8 x 10'5
7 x 105
2 x 10 5
2 x 10"5
Industrial Worker
(Outdoor)
1 x 104
2 x 10 5
83
(Inhalation and
Dermal)
95
T etrachloroethene
7 x 105
1 x 10'5
Noncarcinogenic HI
Resident Farmer or
Residentb
Adult
Child
17
19
11
12
96
100
T etrachloromethane
31
(Adult + Child)
20
(Adult + Child)
Industrial Worker
(Indoor)
16
. 10
98
100
T etrachloromethane
15
10
Industrial Worker
(Outdoor)
15
9
95
(Inhalation)
100
T etrachloromethane
14
9
"Although the resident farmer scenario includes more exposure pathways than the resident, these pathways collectively contribute less than 0.5%
additional risk for carcinogens.
bAdditional pathways for resident farmer collectively contribute less than 0.1% additional risk for noncarcinogens.
COC - contaminant of concern
CTE - central tendency exposure
HI - hazard index
RME - reasonable maximum exposure
-------
1
Ingestion/inhalation contribute almost all of the risk; groundwater is the most important exposure
medium (90 to 100 percent of each category}. PCE had the highest overall carcinogenic risk in each
exposure scenario; tetrachloromethane had the highest noncarcinogenic HI (80 to 90 percent of the
contribution in each category). Because groundwater would contribute most of the carcinogenic and
noncarcinogenic risks, it is the focus of the remedial efforts.
6.8. Remedial Action Objectives
Remedial action objectives are descriptions of how the remedial actions will protect human health and
the environment and achieve the remediation goals.
6.8.1. Soils
To protect human health, the remedial action objective will be to prevent or reduce infiltration and
migration of contaminants that would result in groundwater contamination in excess of remediation
goals. Additionally, soil contaminants should not lead to an aggregate excess cancer risk greater than
1x10"5 or an HI greater than one for occupational exposures.
6.8.2. Groundwater
To protect human health, the remedial action objective will be to prevent ingestion of water with
contaminant concentrations in excess of remediation goals (1x10"4 aggregate cancer risk for chemical
risk and radiological risk combined). To protect environmental health, the objective will be to control
or reduce (to remediation goals) the contaminant concentrations in the aquifer adjacent to OU 1. The
preliminary remediation goals for the groundwater medium are shown in Table 8. This will prevent
contaminant movement into the BVA and ensure that the BVA remains a safe drinking water source.
The specific cleanup level of each contaminant is based on federal primary drinking water standards
(40 CFR 141) and the limits of analytical capability to measure, as discussed in the FS. The point of
compliance for groundwater is outside (south and west) of the road bounding the site sanitary landfill,
as identified in 2 May 1994 correspondence (Attachment B).
7. DESCRIPTION OF ALTERNATIVES
The alternatives analyzed for OU 1 are discussed below. Detailed descriptions of the alternatives are
provided in the OU 1 FS.
EH Program, Mound Plant
Final
MOLNDHM1RODDSA WP 6/2,95
Operable Unit 1, Record of Decision
June 1995
Decision Summary
Page 37
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.
Table 8. Preliminary Remediation Goals
Constituent
Risk-based
PRG* (vb/L)
5DWA
MCL
U»g/Ll
Ohio Drinking
Water Rule
U/g'L)
Maximum
Concentration11
O/g/L)
Estimated
Quantitation
Limit (pg/ll
Proposed
PRG U/g/L!
Lifetime
Risk at
Proposed
PRG
Actinium-227C
0.1
NLd
NL
1.6
0.2
2
2 x 10 B
Chlordane(alpha)
0.06
2
NL
ND
0.05
0.06
1 x 10®
1,2-Dichloroethane
0.1
NL
NL
ND
0.3
0.1
1 x 106
1,2-c/s-Dichtoroethene
60
70
NL
12
1.0
GO
HQ = 1
P1utonium-23Bc
0.2
15®
NL
0.0536
0.2
0.2
1 X 10"6
Plutonium-239/240c
0.2
15e
NL
0.317
0.2
0.6
3x10"6
Tetrachloroethene
1
5
NL
2.5
0.3
5
5 x 10 6
T etrachloromethane
0.2
5
5
ND
1.2
0.2
1 x 10'6
Trichloroethene
2
5
5
ND
1.2
2
1 x 10"6
Trichloromethane
0.2
100
100
14
0.5
2
1 x 10's
Tritium0
900
20,000
20,000
4,220
500
3,000
3 x 1 0"6
Viny) chloride
0.02
2
2
3.6
1.0
1
5* 10 s
"Risk-based PRGs concentration from residential water use scenario. When a contaminant had both carcinogenic and
noncarcinogenic risks, the lower was chosen. Risk-based PRGs were calculated as shown below.
bValues listed are the maximum detected values outside of the remediation area Iwells 71, 154, 155, 377, and 370).
cPicocurles per liter IpCi/LS.
''The proposed MCL for beta and photon emitters is 4 milliroentgen equivalent in man (mrem) ede/yr with a screening level of
50 pCi/L.
"MCL listed is a proposed value for adjusted gross alpha.
MCL - maximum contaminant level
NL - not listed
ND - not detected
PRG - preliminary remediation goBl
SDWA - Safe Drinking Water Act
A'g/L - micrograms per liter
Chemical Carcinogen Risk-based PRG (/yg/L) -
TR x BW x AT x 1000 g/mg
EF x ED x aVF x IRA x SF,] + [IRW x SFJ)
Noncarcinogen Risk-based PRG ifj/L) - TR x BW *AT x 1°°°
EF x ED x
Radionuclide Carcinogen Risk-based PRG (pCi/L) -
VF x IRA ^ IRW
RfE + RfD,
TR
EF x ED x ([VF x IRA x SFJ + [IRW x SFJ)
Where:
TR
BW
AT
EF
ED
VF
IRA
IRW
SF,
SF0
RfDj
RfD„
Target risk (1 x 10'6 for carcinogens, hazard quotient of 1 for noncarcinogens)
Body weight lage-adjusted for carcinogens-59 kg, for noncarcinogens - 70 kg)
averaging time (25,550 days)
exposure frequency (350 days/year)
exposure duration (30 years)
volatilization factor (where applicable = 0.5)
inhalation rate (age-adjusted for carcinogens - 19 m3/day, for noncarcinogens - 20 m3/day)
ingestion rate of water (age-adjusted for carcinogens - 1.8 L/day,
for noncarcinogens - 2 L/day)
inhalation slope factor (chemicals - kg-day/mg, radionuclides 1/pCi)
oral slope factor (chemicals - kg-day/mg, radionuclides 1/pCij
inhalation reference dose (kg-day/mg)
oral reference dose (kg-day/mg!
ER Program, Mound Plant
Final
MOjNDMfcMftCOOSP.We' 6/ 2/95
Operable Unit Record of Decision
June 1995
Decision Summary
Page 38
w
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k
7.1. Common Elements
All alternatives now being considered lor the site will include several common components. Each
alternative includes surface controls, the implementation of institutional controls to limit access to the
site, and long-term groundwater monitoring. Surface controls, such as grading and lining of existing
ditches, will manage the surface water runon and runoff and reduce infiltration. Reducing infiltration
will slow the rate at which contaminants migrate from the unsaturated soil into the groundwater.
Institutional controls will be designed to control land and groundwater use. Such controls can take the
form of access restrictions and fencing around the site to minimize contact with soils and deed
restrictions to prevent groundwater usage onsite and downgradient on property currently owned by
DOE. The site is currently fenced. Appropriate deed restrictions will be obtained at the time the
facility is transferred. The monitoring activities will be conducted to document the effectiveness of
the selected remedy.
Alternatives 3 through 7 include extracting the groundwater for disposal through the Mound Plant
NPDES-permitted outfall. This groundwater extraction will be effective at capturing contaminated
groundwater before offsite migration can occur.
7.2. Description of the Alternatives
The alternatives contain elements that range from limited action through capping, containment, and
in situ treatment. Descriptions of these elements are provided below. More detailed descriptions of
the alternatives are provided in the FS.
The no-action alternative (Alternative 1) involves no additional activities at the site.
The limited-action alternative (Alternative 2) consists, only of the common elements
described above.
The collection-and-disposal alternative (Alternative 3) also encompasses extraction of
groundwater for disposal through the Mound Plant NPDES-permittBd Outfall. Under this
alternative, the soil contamination would be left in place.
Under the alternatives incorporating a treatment option (Alternatives 4 through 7),
groundwater would be extracted and treated onsite to remove VOCs.
Under the capping alternatives (Alternatives 5, 7, and 9), a surface cap of low-permeability
soil would be placed on the ground surface above known waste disposal arEeas that could
be considered potential sources of groundwater contamination. The cap would be
designed for integration into the existing cap for the site sanitary landfill and surface
drainage structures so that erosion and infiltration would be minimized.
ER Program, Mound Plant
Final
MOUKOrM'RODDSA.WF 6/2>9S
Operable Unit 1, Record of Decision
June 1995
Decision Summary
Page 39
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Under alternatives incorporating a subsurface barrier (Alternatives 6 and 7), groundwater
would be contained onsite with a low-permeability subsurface wall around the western and
southern perimeter of OU 1, which would be constructed by the slurry column technique.
Groundwater within OU 1 would be extracted only at a rate sufficient to maintain a
hydraulic gradient across the containment barrier toward OU 1.
Under the in situ treatment alternatives (Alternatives 8 and 9), subsurface permeable
treatment walls composed of a mixture of iron shavings and sand would be installed in the
subsurface downgradient of the site. Slurry columns would serve to direct the flow of
groundwater toward the treatment walls and minimize movement of groundwater offsite.
8. SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES
This section presents a detailed analysis of the alternatives that were considered. Each alternative is
evaluated in detail using nine CERCLA evaluation criteria, which are categorized into the following three
criteria groups:
Threshold Criteria
- Overall protection of human health and the environment addresses whether a remedy
provides adequate protection of human health and the environment and describes how
risks posed through each exposure pathway are eliminated, reduced, or controlled
through treatment, engineering controls, or institutional controls.
Compliance with applicable or relevant and appropriate requirements (ARARs) addresses
whether a remedy will meet all of the ARARs or other federal and stBte environmental
laws and/or justifies a waiver on the basis of technical impracticability.
Primary Balancing Criteria
- Long-term effectiveness and performance refers to expected residual risk and the ability
of a remedy to maintain reliable protection of human health and the environment over
time, once cleanup goals have been met.
- Reduction of toxicity, mobility, or volume through treatment may be used as the
performance measure of the treatment technologies.
- Short-term effectiveness addresses the period of time needed to achieve protection.
Short-term effectiveness also considers any adverse impacts on human health and the
environment that may be posed during the construction and implementation period until
cleanup goals are achieved.
- Implementabillty is the technical and administrative feasibility of remedy, including the
availability of materials and services needed to implement a particular option.
- Cost includes estimated capital, operations, and maintenance costs expressed as net
present worth costs.
ER Program, Mound Plan!
Final
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June 1995
Decision Summary
Page 40
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Modifying Criteria
- State/support agency acceptance reflects aspects of the preferred alternative and other
alternatives that the support agency favors or to which the agency objects, as well as
any specific comments regarding state ARARs or the proposed use of waivers. The
assessment of state concerns may not be complete until after the public comment
period on the RI/FS and Proposed Plan is held.
- Community acceptance summarizes the public's general response to the alternatives
described in the Proposed Plan and in the RI/FS, based on public comments received.
Like state acceptance, evaluations under this criterion usually will not be completed until
after the public comment period is held.
The evaluation of alternatives is summarized in Table 9; cost detail is provided in Table 10. This
section profiles the performance of the selected remedy against the remedial evaluation criteria, noting
how it compares to the other options under consideration. Because the no-action and institutional
controls alternatives, by themselves, do not protect human health and the environment, they are not
considered an option for this site.
8.1. Threshold Criteria
To be considered a viable option, a remedial alternative must meet the threshold criteria or, in the case
of compliance with ARARs, justify a waiver of a particular ARAR.
8.1.1. Overall Protection
All of the alternatives except 1 and 2 would provide adequate protection of human health and the
environment by eliminating, reducing, or controlling risk through treatment, engineering controls, or
institutional controls.
8.1.2. Compliance with ARARs
The chemical-specific and action-specific ARARs are presented . in Attachment B. All alternatives
(except the no-action and institutional controls alternatives) were designed to meet all of the ARARs.
Under the no-action and institutional controls alternatives, ARARs would be exceeded at the point of
compliance. All remaining alternatives would meet their respective ARARs. The selected remedy
treats VOC concentrations in the discharge water from the remediation system and will, in particular,
comply with the Chronic Freshwater Criteria ARARs.
8.2. Balancing Criteria
Once the threshold criteria are satisfied, the balancing criteria are used to weigh the relative merits of
various alternatives. The issues concerning the balancing criteria are displayed in Table 9.
ER Program, Mound Plant
Final
MOUNCI'.M'BOODSA.W B/2.'95
Operable Unit 1, Record of Decision
June 1995
Decision Summary
Page 41
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Z -n m
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Table 9. Summary of Remedial Action Alternative Comparison
Alternative
Short Title
Complies
With
ARARs
Short-term
Effectiveness
Long-term
Effectiveness
Protects
Human
Health and
the
Environment
Reduces
Toxicity,
Mobility,
or
Volume
Implementability
Total Cost
1
No action
No
No
No
No
No
Easy
$0
2
Institutional
No
No
No
No
No
Easy
$3,980,000
3
Collect/
disposal
Yes
Adequate3
Yes
Adequate
Yes
MV
Less difficult
$262,000°
4
Collect/treat/
disposal
Yes
Adequate3
Yes
Adequate
Yes
TMV
Less difficult
$1,740,000°
5
Collect/treat/
disposal/cap
Yes
Adequate6
Yes
Adequate
Yes
TMV
Less difficult
$2,390,000°
6
Contain/collect/
treat/disposal
Yes
Adequate6
Yes
Adequate
Yes
TMV
Moderately
difficult
$2,650,000°
7
Contain/collect/
treat/disposal/
cap
Yes
Adequate6
Yes
Adequate
Yes
TMV
Moderately
difficult
$3,300,000°
8
In situ
groundwater
treatment
Yes
Adequate6
Yes
Adequate
Yes
TMV
More difficult
$1,980,000°
9
In situ
groundwater
treatment/cap
Yes
Adequate6
Yes
Adequate
Yes
TMV
More difficult
$2,630,000°
o
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£
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Table 10. Summary of Detailed Cost Analysis
Alternative
Number
Short Title
Total Capital
Cost"
Annual
Operation and
Maintenance
without
Common Cost"
Present Value of
30-year Annual
Operation and
Maintenance without
Common Cost8
Total Present
Value without
Common Cost"
1
No action
$0
$0
$0
$0
2
Institutional
$139,000
$201,000
$3,840,000
$3,980,000
Each of the following entries is IN ADDITION TO the cost shown for line 2 (Alternative 2).
3
Collect/disposal
$205,000
$3,000
$57,300
$262,000
4
Collect/treat/disposal
$567,000
$61,000
$1,170,000
$1,740,000b
5
Collect/treat/disposal/cap
$857,000
$80,000
$1,530,000
$2,390,000
6
Contain/collect/treat/disposal
$1,330,000
$69,000
$1,320,000
$2,650,000
7
Contain/collect/treat/disposal/cap
$1,620,000
$88,000
$1,680,000
$3,300,000
8
In situ groundwater treatment
$1,650,000
$17,000
$325,000
$1,980,000
9
In situ groundwater treatment/cap
$1,940,000
$36,000
$688,000
$2,630,000
5' 8 Represents the common cost used in each cost estimate.
b Represents highest likely cost for treatment technology.
NOTE: Figures rounded to three significant digits after computations completed.
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-------
8.2.1. Short-Term Effectiveness
Alternatives 5, 7, and 9 provide the greatest short-term effectiveness because, immediately after
installation, the surface cap would prevent contact with contaminated soils. Some dust generation is
expected during installation of the cap; however, this risk could be easily reduced by dust control
methods and worker protection. The cap would also rapidly reduce leachate movement from the
unsaturated zone into the groundwater.
Alternatives 3, 4, 6, and 8, which do not include a surface cap but do include a fence around AreB B,
would have little short-term effectiveness because contact with contaminated soils would not be
completely prevented. Potentially, onsite workers would be exposed to contaminated soils and the
community could potentially be exposed to COCs through airborne dust.
Environmental impacts common to all alternatives include disturbance of biota in the construction
areas. However, these would not be significant environmental impacts.
8.2.2. Long-Term Effectiveness and Permanence
Alternatives 7 and 9 provide the highest degrees of long-term effectiveness and permanence because
they use a subsurface containment system (slurry columns) to passively reduce offsite movement of
contaminated groundwater. Alternative 7 also employs groundwater recovery wells to extract
contaminated groundwater from Area B and to ensure a hydraulic gradient toward Area B.
Groundwater recovery wells would be effective over the long term at fulfilling these tasks. The
permanence of these alternatives would also be considered high because, once the PRGs are met,
groundwater contamination would remain onsite. These alternatives also use a surface cap to
passively reduce leachate movement from the unsaturated zone. This technology would contribute
to the high degree of effectiveness and permanence of these alternatives due to the resultant decrease
in contaminant flux from the unsaturated zone.
Alternatives 6 and 8 also employ subsurface containment systems (slurry columns) around Area B.
However, because these do not implement a surface cap to control contaminant flux from the
unsaturated zone, their permanence would be considered less than Alternatives 7 and 9.
Alternatives 3, 4 and 5, which utilize groundwater recovery wells but no subsurface containment,
would be less effective at preventing offsite movement of contaminated groundwater. Even if properly
monitored and adjusted according to changing hydrogeologic conditions, a small amount of
groundwater could potentially not be captured it one or more recovery wells were shut down for
maintenance.
ER Program, Mourn) Plant
Final
MO'JKDMMIRODCSA.WP 6/2'95
Operable Unit 1, Record of Decision
June 1995
Decision Summary
Page 44
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8.2.3. Overall Protection of Human Health and the Environment
Alternatives 5, 7, and 9 provide adequate protection of human health and the environment by reducing
the risk of soil contact and contaminated groundwater ingestion. Alternatives 3, 4, 6, and 8 reduce
risk of contaminated groundwater ingestion but provide minimal reduction of soil contact risk.
Alternative 1 (no action) provides no protection of human health and the environment. Alternative 2
provides minimal reduction of the risk of contact with soil. Alternative 2 also provides some reduction
of risk through groundwater ingestion onsite, but there is some uncertainty about the prevention of
offsite groundwater ingestion.
8.2.4. Reduction of Mobility. Toxicity, and Volume Throuah Treatment
All alternatives except 1, 2, and 3 reduce the mobility, toxicity, Bnd volume of contaminated
groundwater by employing UV/oxidation water treatment technology prior to its discharge through the
NPDES-permitted outfall. This technology is reliable with proper operation and maintenance.
Alternatives 1 (no action) and 2 (institutional controls) do not reduce mobility, toxicity, or volume of
contaminated groundwater through treatment. Alternative 3 reduces only contaminant volume and
mobility in the groundwater by implementing groundwater extraction.
8.2.5. Implementabilitv
Technically, Alternative 2 would be the easiest to implement because it only involves construction of
a fence. However, this alternative would be the most difficult to implement administratively because
of uncertainties involving acquisition of land or water rights to prevent groundwater ingestion.
Alternatives 3, 4, and 5 could be implemented using standard construction techniques and practices.
The water treatment technology required in Alternatives 4, 5, 6, and 7 is not widely used but, because
it has been put into practice at several sites and is relatively uncomplicated to operate, it should be
readily implementable.
Alternatives 5, 7, and 9, which involve the surface cap, would be less implementable than their
counterparts that do not include a surface cap (Alternatives 4, 6, and 8). To make augmentation of
the existing cap feasible, the low-permeability soil option was chosen since it was the best match to
the existing cap and could be used to extend the cap over the desired areas with less disruption to the
current containment system. Given the steep sides of the existing landfill, however, an added degree
of difficulty exists in the design and implementation of the surface cap extension.
ER Program, Mound Plant
Final
V.OUNCHM1P.ODDSA.WP 6(J.'95
Operable Unit 1, Record of Decision
June 1995
Decision Summary
Page 45
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Alternatives 6 and 7, which involve construction of a subsurface barrier with slurry columns around
Area B, would not be as readily impiementable as the previous alternatives. Prior to slurry column
installation, a soil-boring program for contaminant sampling and geotechnical testing must be
conducted. The slurry column installation would then be implemented using common construction
practices.
Alternatives 8 and 9, which involve subsurface barriers and a subsurface permeable treatment wall,
would be less impiementable than Alternatives 6 and 7 because treatability studies would be required
to design the permeable treatment wall. The slurry column construction for this alternative would be
the same as described above.
9. SELECTED REMEDY
The selected remedy for controlling contamination from the soils and groundwater at OU 1 is
Alternative 4 — Collection, Treatment, and Disposal of Groundwater. As discussed previously, the
common elements of surface water controls, institutional controls to limit site access, and long-term
groundwater monitoring will be part of the remedy as well. Based on groundwater studies conducted
during the FS, it is currently envisioned that the collection (groundwater extraction) system will consist
of two wells pumping at a combined rate of 45 gallons per minute. Additional groundwater modeling
will be conducted during the remedial design phase, which will establish optimum location and pumping
rates for the extraction wells. Some changes may be made to the remedy as a result of the remedial
design and construction process. Such changes, in general, will reflect modifications resulting from
the engineering design process.
Based on current information, this alternative would meet the USEPA remedial evaluation criteria. The
alternative meets the threshold criteria (is protective of human health and the environment and satisfies
all the ARARs) and satisfies the primary balancing criteria (short- and long-term effectiveness; reduction
of toxicity, mobility, or volume; and implementability) for the least cost. Because it reduces toxicity
and volume and controls mobility, the alternative also protects the Mound Plant production wells. The
preferred alternative would be effective in capturing contaminated groundwater beneath the OU 1 site
before it migrates offsite. The groundwater pump-and-treat system will reduce the contaminant mass
in the subsurface and will continue to operate until groundwater meets the Preliminary Remediation
Goals specified in Table 8. It is difficult to predict how long this will take, but for costing purposes,
it was assumed the system would operated for a period of 30 years. The treatment system specified
for this site could efficiently remove the VOCs to the preliminary remediation goals listed in Table 8.
All extracted groundwater would be treated to levels that will comply with the requirements of the
Mound Plant NPDES Permit.
ER Program, Mound Plant
Final
MOUND'WIRCDOSA.WP 6/2/95
Operable Unit 1, Record of Decision
June 1 995
Decision Summary
Page 46
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The contemplated treatment system will primarily consist of a unit designed to remove VOCs from the
water prior to discharge. Final determination of all required treatment will be made as part of the detail
design. There are several potentially viable treatment trains for VOCs, including cascade aeration, UV
oxidation, and conventional air stripping; all offer the possibility of adequate treatment. Additionally,
the CERCLA process allows for and promotes the use of innovative technologies whenever potentially
practicable and cost-effective. Final selection of technologies will be made during remedial design,
when any of these systems may be determined to be optimal. Cascade aeration, as well as the other
treatment trains, constitutes best available treatment.
Thus, the selected remedy —collection, treatment, and disposal—will provide a cost-effective remedial
option that is easy to implement and that will adequately protect human health and the environment.
Following issuance of the ROD, three kinds of changes that require documentation can be made to the
selected remedy. These are as follows:
Minor changes that require differences to be documented in the post-ROD file.
Significant changes that require the development of an explanation of significant
differences for inclusion in the Administrative Record. Significant changes are those that
modify or replace a component of the selected remedy.
Fundamental changes that require the development of a ROD amendment and, thus,
additional public comment. Fundamental changes are changes of the selected remedy that
do not reflect the ROD with regard to scope (e.g., overall approach), performance, or cost.
At the time DOE proposes the specific treatment technology to be used, DOE, in consultation with
USEPA and OEPA, will determine whether changes need to be made in the ROD and will implement
the specified modification procedures.
10. STATUTORY DETERMINATIONS
The selected remedy protects human health and the environment, complies with federal and state
requirements that are legally applicable or relevant and appropriate (ARAR) to the remedial action, and
is cost-effective. A list of ARARs that will be attained by the selected remedy, along with the "To Be
Considered" (TBC) item that was used, is provided as Attachment B. In implementing the selected
remedy, DOE, USEPA, and OEPA have agreed to consider a procedure that is not legally binding. In
implementing the selected remedy, DOE, USEPA, and OEPA have agreed to consider as a TBC the
OEPA policy on wastewater discharge resulting from cleanup of response action sites contaminated
with VOCs.
ER Program, Mound Plant
Final
MCUNQHM1RDDDS A.WP 6/2 *95
Operable Unit 1, Record of Decision
June 199B
Decision Summary
Page 47
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This remedy uses permanent solutions and alternative treatment technologies to the maximum extent
practicable for this site, and satisfies the statutory preference for treatment as a principal element of
the remedy. While the remedy calls for treatment of contaminated groundwater, treatment of soil at
the site was not found to be practicable. The fact that the source of contamination is diffuse and no
substantive onsite soil hot spots exist precludes a remedy consisting of excavation and treatment of
contaminants in soil.
Because this remedy will result in hazardous substances remaining onsite above health-based levels,
a review will be conducted within 5 years after commencement of the remedial action to ensure that
the remedy continues to provide adequate protection of human health and the environment.
11. DOCUMENTATION OF SIGNIFICANT CHANGES
The OU 1 Proposed Plan was released for public comment in November 1994. The Proposed Plan
identified Alternative 4 (Collection, Treatment, and Disposal) as the preferred alternative for
groundwater remediation. DOE reviewed all written and verbal comments submitted during the public
comment period. Upon review of these comments, it was determined that no significant changes were
necessary to the remedy as originally identified in the Proposed Plan.
ER Program, Mound Plant
Final
MOCND1\M1HODDSA WP 6/2^95
Operable Unit 1, Record of Decision
June 1995
Decision Summary
Page 48
f
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RESPONSIVENESS SUMMARY
-------
CONTENTS
RESPONSIVENESS SUMMARY 50
1. OVERVIEW 50
2. BACKGROUND ON COMMUNITY INVOLVEMENT 50
3. SUMMARY OF PUBLIC COMMENTS RECEIVED DURING PUBLIC COMMENT PERIOD AND
DOE RESPONSES 52
3.1. Summary and Response to LocbI Community Concerns 52
3.2. Comprehensive Response to Specific Legal and Technical Questions 59
4. REMAINING CONCERNS 59
ER Program, Mound Plant
Final
MDUNDUMIRODftSA.TC 6,1 36
Operable Unit 1, Record of Decision
June 1995
Contents
49
/
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RECORD OF DECISION
OPERABLE UNIT 1
AREA B. MOUND PLANT. OHIO
June 1995
RESPONSIVENESS SUMMARY
1. OVERVIEW
At the time of the public comment period (15 November 1994), DOE had identified a preferred
alternative for OU 1, Area B. The recommended alternative, as published tn the Proposed Plan,
consisted of collection, treatment, and disposal of groundwater. The treated groundwater would be
released to the Great Miami River.
Judging from the limited number of comments received during the public comment period, the citizens
and other interested parties did not question the overall remediation strategy. Comments were directed
to the nature and need for treatment, as well as the manner in which the treatment system would be
operated.
These sections follow:
Section 2, Background on Community Involvement.
Section 3, Summary of Comments Received During the Public Comment Period and DOE
Responses.
- Section 3.1, Summary and Response to Local Community Concerns.
- Section 3.2, Comprehensive Response to Specific Legal and Technical Questions.
Section 4, Remaining Concerns.
Attachment C, Community Relations Activities for OU 1, Area B.
2. BACKGROUND ON COMMUNITY INVOLVEMENT
Community reaction to Mound Plant has been mixed. Unlike most sites that handle nuclear material
and hazardous chemicals, Mound Plant does not sit in an isolated location. The plBnt can be seen from
downtown, schools, farm fields, parks, and homes. The backyards of a few Miamisburg residences
ER Program, Mound Plant Operable Unit 1, Record of Decision Responsiveness Summary
Final June 1995 Page 50
MOUNDUMIRaDKSA.WP W1DS
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end at Mound Plant's fence. Also, Mound Plant has had a highly visible community image, with a long
record of community service and philanthropy. Historically, the majority of the local residents have
viewed Mound Plant as no threat to the community.
Community involvement for OU 1 has been integrated with community involvement activities for the
Mound Plant Site as a whole. The Mound Plant CERCLA Community Relations Plan, published in 1990,
provided for soliciting comment while informing the public about planned and ongoing actions. The
public information activities are carried out through quarterly CERCLA public meetings and by periodic
publication of a newsletter, the Superfund Update.
As the field investigation of OU 1 was completed, public information activities directed toward OU 1
were initiated. Specific items are:
An update on the field investigation was included in the October 1993 Superfund Update.
The budget priorities for OU 1 and the balance of the CERCLA program were the subject
of a workshop at the October 1993 CERCLA public meeting.
A briefing on the site conditions and environmental issues relating to OU 1 was presented
at CERCLA public meetings on 14 June 1993 and 22 September 1994.
The OU 1 RIR, containing results and interpretations of field investigations, was placed in
the public reading room in May 1994.
A brochure, Environmental Restoration at Mound, was published in July 1994 and included
a short description of OU 1. A brochure providing more detail on OU 1 was published in
September 1994.
A fact sheet announcing the availability of the FS and the Proposed Plan was published in
November 1 994.
Public comments were solicited and received at a public hearing on 8 December 1994.
The transcript of that hearing is available in the public reading room.
In response to comments, a second fact sheet was published in December 1994.
The public comment period remained open until 31 January 1995.
ER Program, Mound Plant
Final
M0UND1W 1RCORSA.WP 6/2*95
Operable Unit 1, Record of Decision
June 1995
Responsiveness Summary
Page 51
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3. SUMMARY OF PUBLIC COMMENTS RECEIVED DURING
PUBLIC COMMENT PERIOD AND DOE RESPONSES
The public comment period extended from 15 November 1994 through 31 January 1995. A public
meeting and hearing was held on 8 December 1994. Two comments were received at the hearing.
Two sets of written comments were received from technical advisors to Miamisburg Environmental
Safety and Health (MESH). The state of Ohio raised one additional technical issue.
3.1. Summary and Response to Local Community Concerns
1. Selection of Alternative 4 over Alternative 3.
At the 8 December 1994 public meeting for the OU 1 Proposed Plan, a question was raised concerning
Table 1 on page 9 of the Proposed Plan. The question concerned the apparent similarity of
Alternatives 3 and 4, with the exception of maximum total cost.
DOE Response: Table 9, in the ROD, updates and clarifies Table 1 by identifying the reduction of
toxicity, mobility, or volume of contaminants that each alternative addresses. Alternative 3 meets the
mobility and volume reduction statutory preference for selecting remedial actions (page 4-10 of the
OU 1 FS). It does not address toxicity reduction, which is also a statutory preference for selecting
remedial actions. Therefore, DOE, in consultation with the USEPA and OEPA, has determined that
Alternative 4, which includes treatment to reduce toxicity, is preferable. The reduction of toxicity,
mobility, or volume for Alternative 4 is explained on page 4-14 of the FS.
Guidance from the OEPA indicates that wastewater discharges resulting from cleanup of response
action sites contaminated with VOCs need to be treated with the best available technology for toxicity
reduction. The state of Ohio believes that Alternative 3 does not meet those requirements.
The NCP (40 CFR 300) identifies two additional "modifying criteria," which are (1) state acceptance
and (2) community acceptance. Based on the state's position on Alternative 3, Alternative 4 was
chosen as the preferred alterative. This Responsiveness Summary incorporates an evaluation of
community acceptance based on public comments.
Efi Program, Mound Plant
Final
WOUUDliMIP.ODRSA.W® 8/2/35
Operable Unit 1, Record of Decision
June 1995
Responsiveness Summary
Page 52
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2. Compatibility with overall remedy for the Site.
At the 8 December 1994 public meeting for the OU 1 Proposed Plan, a question was raised whether
the remedy for OU 1 would help or hinder remedial action for the Site as a whole. The
recommendation was made to "put your arms around the whole project."
DOE Response: DOE is ultimately concerned with a remedy for the Mound Plant CERCLA Site bs a
whole. The Site has been broken down into separate OUs to facilitate the planning and investigation.
OU 1 is the first unit to be considered for final remedial action. The other OUs also likely will be
considered one at a time to maintain a reasonable rate of progress. However, each removal action,
interim remedial action, or final remedial action is evaluated to ensure that it is unlikely to interfere with
any overall remedy for the complete Site.
The selected remedy for OU 1 will withdraw groundwater from beneath and immediately adjacent to
OU 1. A small portion of the groundwater that now flows down the tributary valley and enters the
BVA could be diverted into the remediation wells. The effect of the remediation on the hydraulic
performance of the plant production wells is expected to be immeasurably small. Thus, the selected
remedy is expected to be compatible with potential remedial actions in other parts of the plant.
Further, it should support or assist in controlling migration of contamination, thus directly supporting
a range of alternatives. As other portions of the plant are considered for remediation, DOE will
reconsider this issue.
3. Peter Townsend, MESH Technical Advisor, stated, "I conclude that remedial alternative 4 is the
most reasonable alternative for clean-up of the landfill and overflow pond area. Alternative 4 will
involve ground water collection and treatment, and appears capable of preventing further
contamination of groundwater in the immediate area of the overflow pond and existing landfill."
Mr. Townsend went on to comment on the occurrence of 1,1,1-TCA in the BVA. He agreed with the
assertion in the RIR that OU 1 was not the source of this contaminant, but suggested that it could still
be the result of Mound Plant activities. He identified the NPDES 001 outfall pipe as a possible source,
since rt had (formerly) been an unsealed, butted cement pipe. Mr. Townsend recommended that
consideration of this possible source be considered in the OU 1 FS or a future document.
DOE Response: This commentor agrees with the DOE selection of the remedial alternative presented
in the OU 1 Proposed Plan. However, concern is raised regarding offsite contamination, which DOE
has concluded is not related to OU 1 or, in fact, to Mound Plant. The commentor misinterprets a
statement on page 2-20 of the RIR and concludes that VOC contamination was discovered and caused
ER Program. Mound Plant Operable Unit 1, Record of Decision Responsiveness Summary
Final June 1995 Page 53
MDU«1\M1HDDRSA.WP 6195
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some private residences to bB connected to Miamisburg city water. The statement says that "In
January 1988, residences that used groundwater from wells 0901, 0902, 0903, 0906, 0907, and
0908 (Figure 2.6 in the RIR) were connected to Miamisburg city water due to local organic
contamination." This group of wells was owned by the operator of a trailer park, who supplied
drinking water to the residents. This system met the definition of a community water system and was
subject to the Safe Drinking Water Act (SDWA) regulations. It is DOE's position that these residences
did not discontinue use of these wells as a result of VOC contamination originating from Mound Plant.
The switch to city water was caused, we believe, by the owner's difficulty and expense involved with
the testing and operating conditions required to comply with SDWA regulations. During 1986 to 1988,
Mound Plant conducted at least six separate sampling events for wells 0901 through 0908. No VOCs
were detected in any of these events; specifically, 1,1,1-TCA was not detected. This commentor also
speculates that the source of thB alleged 1,1,1-TCA plume was the Mound Plant NPDES outfall 001
pipeline. To clarify the situation, Mound Plant drawings and long-time employees were consulted.
Drawings indicate that the pipeline is 12-inch-diameter vitrified clay pipe, of bell and spigot
configuration, from west of Cincinnati-Dayton Pike to the river. This configuration would require each
joint to be filled with mortar to allow proper alignment. As part of a site-wide program to upgrade
sewer lines, this pipeline was slip-lined with a continuous plastic liner in approximately 1980 to 1981.
This was done as a good management practice, not because of a known contamination problem. No
VOC contamination has been detected from the wells (0127, 0128, 0302, 0303, 0343, 0383) located
due south of the 001 outfall pipe, which confirms there is no VOC contamination as a result of possible
leakage from the 001 discharge pipe.
4. Jeff Fisher, MESH Technical Advisor, provided the following comments:
a. No remediation goals (except ARARs were described for surface and ground water, surface and
deep soil, sediment and air. Clean up or treatment is fine, but goals need to be established and agreed
upon by the USEPA, OEPA, Mound, and Stakeholders. A clear assessment of the treatment system's
ability to meet cleanup goals is necessary. Without a target you are just "shooting arrows at a wall."
DOE Response: All of these issues are addressed in the OU 1 FS, which was released for public review
with the Proposed Plan. Remediation goals were established and cleanup targets were agreed upon
in extensive discussions among Mound Plant, DOE, USEPA and OEPA.
b. Off site contamination needs to be addressed and workable solutions discussed by the Mound,
regulators, and stakeholders. Environmental contamination extends beyond the boundaries of Mound.
ER Program, Mound Plant
Final
l/OUNCliMlROO^SA.W^ 6'2v9E
Operable Unrt 1, Record of Decision
June 1995
Responsiveness Summary
Page 54
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DOE Response: Offsite issues are being addressed through the OU 9 (site-wide) RI/FS process, as well
as through additional OUs (such as the Miami-Erie Canal). Since conditions at OU 1 do not lead to
offsite contamination, it is not addressed in the current documents.
Mr. Fisher went on to address comments to the OU 1 RIR, which was placed in the reading room in
May 1994. Although not pertinent to the Proposed Plan, the comments and responses are provided
below.
a. Please explain the concept of "background" as it pertains to cleanup of chemicals and radionuclides.
Is it US EPA policy to use background values obtained from the Mound site? How are these used or
compared to background values obtained from sites distant from the Mound?
DOE Response: Chemical and radiological background for the Mound Plant Site is being defined in a
series of data reports published as part of the OU 9 (site-wide) Rl. The background data for surface
soils were published in 1994 {Background Soils Investigation Soil Chemistry Report, Technical
Memorandum, Revision 2, September 1994). This document is available in the public reading room.
Background statements for groundwater, surface water, and sediments are being prepared. All
background will be based on data from the vicinity of, but beyond the influence of, Mound Plant. Use
of background data will be on a case-by-case basis. No reliance on background was used in selecting
the remedy for OU 1.
b. For toxicity values that reference the ECAO [Environmental Criteria and Assessment Office], please
supply written documentation showing the derivation of the toxicity value. Please state what year of
HEAST tables were cited. Are Heast tables prior to 1994 used?
DOE Response: Toxicity values were obtained from the USEPA, as cited in the text and Appendix J
of the OU 1 RIR. No independent derivation of toxicity was made, so no additional documentation is
available. HEAST tables from 1993 were used, since this effort was completed in 1993.
c. There are several typographical errors, but the errors did not detract from the intent of the
document.
DOE Response: Noted.
ER Program, Mound Plant
Final
MOUfOnMlRODRSA WP 6/2*95
Operable Unit 1, Record of Decision
June 1995
Responsiveness Summary
Page 55
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d. The overflow pond appears to be without adequate analytical data and was not included in the risk
assessment. Without this added to the baseline risk assessment, the baseline risk assessment is
inadequate and does not address all important pathways of exposure.
DOE Response: As discussed in the RIR, the overflow pond is part of the plant drainage system, which
is being studied as part of the OU 9 investigation. The limited data available suggest that the overflow
pond is not a significant direct source of contamination to the aquifer system. The pond water and
sediment are not highly contaminated, and the leakage through the liner is not anticipated to be
significant. These issues are addressed in sections 4.2 and 4.4.4 of the RIR. The pond is not an
important pathway of exposure for OU 1.
e. The documents pertaining to OU 1 need to be available to the public in draft form. This is a very
serious problem that needs to be corrected.
DOE Response: All documents are reviewed in draft by both regulatory agencies (USEPA and OEPA),
who approve the final versions prior to public release. This is consistent with CERCLA guidance.
5. The following written comments were received from an anonymous reviewer of the OU 1 Proposed
Plan:
a. Are the Miami Erie Canal sediments the only potential source of tritium in the BVA?
DOE Response: No. The canal is the major source, but small amounts of tritium have also been
detected in wells in the Old Burn Area and Old Landfill Area.
b. What proof do you have that Mound is the source of the VOC contamination presently detected
in the BVA?
DOE Response: The highest levels of VOCs have been detected onsite in the OU 1 location. Historical
Mound well monitoring data also confirm this,
c. Are there any known current tritium sources that may eventually reach the BVA? Are there any
known current tritium sources that may reach the canal?
ER Program, Mound Plant
Final
RGDflSA. WP 6-'2'95
Operable Unit 1, Record of Decision
June 1995
Responsiveness Summary
Page 56
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DOE Response: c1) Yes, under the SW Building. However, it is unlikely that the SW Building tritium
source will reach the BVA. c2) Yes, tritium reached the canal as a result of Mound discharging tritiated
plant water in the Mound drainage ditch that flows into the canal.
d. What are the tritium levels in the main hill seeps?
DOE Response: The highest levels are in the low 100s nanocurie per liter range. The seeps are not
a threat to the aquifer.
e. What historic maximum levels of VOCs were detected in the upstream aquifer (from the Mound
Plantl during a Mound sampling/analysis event or "other's" sampling/analysis event?
DOE Response: The observed levels of VOCs in the background wells (completed in the BVA) are as
follows:
Chemical
Range of Detected
Concentrations
(//g/L)
Mean of Concentrations
O/g/L)
1,1,1-TCA
0.46 - 2.3
0.53
1,2-c/'s-DCE
1.1 - 1.1
0.55
PCE
11.-12.
2.21
Trichloromethane (chloroform)
0.50 - 0.57
0.30
f. What are thB current levels of VOCs upstream from Mound Plant?
DOE Response: The OU 9 Groundwater Sweeps Report, dated January 1995, showed the following
monitoring well data:
Well 011B 0.68/;g/L 1,2-Dichloroethane
Well 0137 1.6/;g/L Trichloroethane
Well 0137 0.58 fjg/L Trichloromethane (chloroform)
Well 0138 0.53/;g/L 1,2-Dichlorethene
Well 0138 6.0 fjg/L Acetonitrile
Well 0138 0.58/;g/L Trichloromethane (chloroform)
Well 0138 9.9 fjgli. Trichloromethane (chloroform)
Well 0327 2.3 /jg/L 1,1,1-Trichloroethane
Well 0327 12.0 fjg/L Tetrachloroethene
Well 0327 0.50/;g/L Trichloromethane (Chloroform)
Well 0328 1.1 1,2-c/s-Dichloroethene
Well 0328 9.0 fjg/L Bis (2-Ethylhexyll Phthalate
Well 0332 8.9 )ug/L Dichloromethane (Methylene Chloride)
ER Program, Mound Plant
Final
MOUND1*M1RODRSA-WP 6/2^95
Operable Unit 1, Record of Decision
June 1995
Responsiveness Summary
Page 57
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g. What ground water model was used to determine the contribution of VOC contamination from the
Mdund historic landfill verses the historic upstream VOC contamination?
DOE Response: For the VOCs, the Darcy Model was used.
h. How does the OU 4 canal remediation schedule, the OU 1 remediation schedule and the OU 2
remediation schedule tie into one another?
DOE Response: Because OU 1 groundwater contamination is the reason the Mound site was put on
the NPL, or Superfund, OU 1 has been given a high priority for cleanup by the DOE. The OU 1 VOC
contamination problem is a result of past disposal practices in OU 1 and is not interactive with the
other Mound Plant OU schedules.
i. Will all other known sources of VOCs be completely remediated prior to the implementation of the
OU 1 Proposed Plan?
DOE Response: No. However, at this time no other plant VOC sources are impacting OU 1.
j. Do you plan to remediate OU 4 (the canal), contain the main hill seeps (OU 2), or remediate the VOC
contaminated soils in the landfill prior to remediating the aquifer?
DOE Response: j1) No. OU 2 and OU 4 are not affecting OU 1 (see response to h). j2) The site
sanitary landfill and overflow pond overlie most of OU 1, making large-scale excavation prohibitive.
k. What are the calculated risks (cancer) for the no-action alternative for OU 1?
DOE Response: The highest overall risk for the onsite resident is 5x10"4.
I. What is the total cost for the OU 1 Proposed Plan implementation?
DOE Response: The estimated cost for the proposed remedy, collection, treatment, and disposal is
$1,740,000. This includes installation costs and annual operations and maintenance costs for an
estimated 30-year remediation cycle.
m. What long term ground water monitoring and sampling will be necessary after remediation is
complete? Is there sufficient Congressional budget available to support the long term monitoring work?
DOE Response: ml) Monitoring and sampling requirements after OU 1 remediation is completed will
be determined based on USEPA groundwater regulatory guidance. m2) Budget provisions have been
made for this work, but this funding is subject to change.
ER Program, Mound Plant
Final
MOUNCV.M1AOORSA.WP 6^2/95
Operable Unit 1, Record of Decision
June 1995
Responsiveness Summary
Page 58
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n. What is the cost for the long term monitoring and sampling in the current five-year plan? How
much will the long term monitoring and sampling cost?
DOE Response: No long-term monitoring and sampling funding has been specifically identified in the
OU 1 5-year plan. Costs for the long-term monitoring and sampling after OU 1 is remediated will be
determined based on USEPA groundwater guidance requirements (see response to ml.
o. Has OEPA and US EPA approved the proposed remedial actions based on risk concerns?
DOE Response: Yes. The Proposed Plan preferred alternative has been approved by both USEPA and
OEPA.
p. What risk level is acceptable as a no action level by Ohio EPA for tritium? for VOCs? for tritium
and VOCs based on levels found in the BVA?
DOE Response: The acceptable USEPA cancer risk levels are 1x10"4 to 1x10"6.
q. What risk level is acceptable as a no action level by US EPA for tritium? for VOCs? for tritium and
VOCs based on levels found in the BVA?
DOE Response: The acceptable USEPA CBncer risk levels Bre 1x10"4 to "IxlO"6.
r. What levels of risk are necessary for the "no action alternative" to be approved by the Ohio EPA
and US EPA regulators assigned to oversea work at Mound? at WPAFB?
DOE Response: The acceptable USEPA cancer risk levels are 1x10"4 to 1x10"®.
3.2. Comprehensive Response to Specific Legal and Technical Questions
As part of its continuing review of the OU 1 FS and Proposed Plan, the OEPA and the Regional Air
Pollution Control Authority (RAPCA) examined the need for air-related permits for the remedy. These
agencies suggested that an application to and review by RAPCA are appropriate. Subsequent
conversations and correspondence confirmed that neither a permit application nor a design review is
needed.
4. REMAINING CONCERNS
None.
ER Program, Mound Plant
Final
MOUND*\MtRCDRSA.WP ft/2/95
Operable Unit 1, Record of Decision
June 1995
Responsiveness Summary
Page 59
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ATTACHMENT A
STATE CONCURRENCE LETTER
-------
OhbEFft
State of Ohio Environment*] Protection Agency
rmgTAPmtts:
mUC ADOWIM:
1800 WaterMark Drive
Columbus, OH 43215-1099
TELE: (614) 644-3020 FAX: <614)644.2329
P O Box 1049
Columbus, OH 43216-1049
May 22, 1995
RE: US DOE MOUND
OPERABLE UNIT 1
RECORD OF DECISION
CONCURRENCE LETTER
Mr. Valdas Adamkus
Regional Administrator
US EPA Region V
77 West Jackson Boulevard
Chicago, Illinois 60604-3590
Mr. J. Phil Hamric
Manager, Ohio Field Office
US Department of Energy
P.O. Box 3020
Miamisburg, Ohio 45343-3020
Dear Mr. Adamkus and Mr. Hamric:
The Ohio Environmental Protection Agency (Ohio EPA) has received and reviewed the April
1995 Operable Unit 1 (OU1) Record of Decision (ROD) for the DOE Mound Superfund site in
Montgomery County.
The OU1 ROD is the first ROD to be completed for the operable units at the DOE Mound. This
remedial action is not the final remedial action for the DOE Mound site, but is intended to be a
final remedial action for OU1. Decisions regarding remedial actions for other portions of the site
are being addressed in other operable units, which will ultimately be considered in a Site-wide
Remedial Investigation and Feasibility Study, which are in progress. A decision on the final
remedial action for the DOE Mound Site will be made in a subsequent decision-making process.
The OU1 ROD addresses groundwater contamination by preventing migration of contamination
(volatile organic compounds) toward the DOE Mound production well. The selected remedial
action will resuh in the minimization of exposure to potential receptors of the groundwater
contamination. The selected alternative includes the following components:
Installation of two groundwater extraction wells within OU1, using
standard equipment and procedures. Specifics regarding the design of the
extraction system will be determined in the Remedial Design.
Treating the extracted groundwater to remove volatile organic compounds
and other constituents, as required, using cascade aeration, ultraviolet
oxidation, conventional air stripping, or other suitable treatment units
including innovative technologies which will achieve the remedial
objectives.
Prrtftd on RtcvcM P«p«'
EPA 1613 (rav. 1/95)
George V. Voinovicti, Governor
Donald R. Schregardus, Director
-------
Mr. Adamkus & Mr. Hamric
Page 2
* Discharging the treated groundwater to the Great Miami River through the
existing plant NPDES outfall or a new outfall. Permit modifications may
be needed to accommodate the final design of the remedy.
The estimated present cost of the selected remedy is $706,000 in 1995 dollars. The estimated
annual present worth of operation and maintenance costs are $1,170,000 for a period of 30 years.
Ohio EPA concurs with the selected remedy based upon this review. Since the selected remedy
dues not. involve establishment or modification of the site sanitary landfill, Ohic Administrative
Code 3745-27-07 is not considered to be Applicable or Relevant and Appropriate (ARAR),
although it would be a potential ARAR for other OU1 remedies.
Because this remedy may result in hazardous substances remaining onsite above health-based
levels, a review will be conducted within five years after commencement of this remedial action to
ensure that the remedy continues to adequately protect human health and the environment
Sincerely,--,
¦Donald R. Schregardi
Director
DRS/klf
cc: Jenny Tiell, Director's Office
Tim Fischer, TJSEPA Region V
JeffHurdley, OEPA Legal
Graham Mitchell, OEPA/OFFO
Jan Carlson, OEPA/DERR
Warren Sherard, DOE MB
Oba Vincent, DOE MB
Art Kleinrath, DOE MB
Brian Nickel, OEPA/OFFO
Ruth Vandegrift, ODH
Ray Beaumier, OEPA/DERR
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ATTACHMENTB
ARARs TABLES
-------
j ti m
«- w
Table 1. State Chemical-Specific ARARs for OU 1
Regulation Title or
Subject/Revised Coda
Saction and Pertinent
Paragraph
Regulation Description
Regulation Application
ARAR
Comment*
Prohibits Violation of
Air Pollution Control
Rules/3704.05 A-l
Prohibits emission of an air contaminant in violation of
Section 3704 or any rule, permit, order, or variance issued
pursuant to that section of the ORC.
May pertain to any site where
emissions of an air contaminant occur
either as a preexisting condition of the
site or as a result of remedial activities.
Should be considered for virtually all
sites.
ARAR
Implementation of the substantive
provisions of state air requirements as
ARARs is required by Section 121(d) of
CERCLA.
Handling Low-Level
Radioactive Waste
Prohibited/3734.02.7
A,B
A) Prohibits commingling low-level radioactive waste with
any type of solid, hazardous, or infectious waste.
B) No owner or operator of a solid, infectious, or
hazardous waste facility shall accept any radioactive
waste for transfer, storage, treatment, or disposal.
Pertains to all sites at which low-level
radioactive waste has come to be
located.
ARAR
Radioactive wastes generated as part of
remedial actions at OU 1 will be managed
separately from non-radioactive materials.
"Five Freedoms" for
Surface Water/
3745-1-04 A,B,C.D,E
All surface waters of the state shall be free from:
A) Objectionable suspended solids.
B) Floating debris, oil, and scum.
C) Materials that create a nuisance.
D) Toxic, harmful, or lethal substances.
D) Nutrients that create nuisance growth.
Pertains to discharges to surface
waters as a result of remediation and to
any onsite surface waters affected by
site conditions.
ARAR
Surface water bodies subject to quality
Criteria standards do not occur within
OU 1. Alternatives that involve discharge
to surface water will be addressed in
action-specific ARARs.
Antidegradation Policy
for Surface Water/
3745-1-05 A,B,C
Prevents degradation of surface water quality below
designated use or existing water quality. Existing instream
uses shall be maintained and protected. The most
stringent controls for treatment shall be required by the
director of the USEPA for all new and existing point source
discharges. Prevents any degradation of "State Resource
Waters."
Pertains to discharges to surface water
as a result of remedial action and to
any surface water affected by site
conditions.
ARAR
Surface water bodies subject to quality
criteria standards do not occur within OU
1. Alternatives that involve discharge to
surface water will be addressed in action-
specific ARARs.
Mixing Zones for
Surface Water/
3745-1-06 A.B
A) Presents the criteria for establishing non-thermal mixing
zones for point source discharges.
B) Presents the criteria for establishing thermal mixing
zones for point source discharges.
Applied as a term of discharge permit
to install.
ARAR
Alternatives involving direct discharge will
comply.
Water Quality Criteria/
3745-1-07 C
Establishes water quality criteria for pollutants that do not
have specific numerical or narrative criteria identified in
Tables 7-1 through 7-15 of this rule.
Pertains to discharges to surface
waters as a result of remedial action
and any surface waters affected by site
conditions.
ARAR
Surface water bodies subject to quality
criteria standards do not occur within OU
1. Alternatives that involve discharge to
surface water will be addressed in action-
specific ARARs.
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Table 1. (page 2 of 5)
Regulation Title or
Subject/Revised Code
Section and Pertinent
Paragraph
Regulation Description
Regulation Application
ARAR
Comments
Particulate Ambient Air
Quality Standards/
3745-17-02 A,B,C
Establishes specific standards for total suspended
particulates.
Pertains to any site that may emit
measurable quantities of particulate
matter (both stack and fugitive).
Consider for sites that will undergo
excavation, demolition, cap installation,
clearing and grubbing, incineration, and
waste fuel recovery.
ARAR
Air emissions may be involved as part of
the treatment in several of the
alternatives. Alternatives involving air
emissions will be coordinated with USEPA
and OEPA to ensure particulate emissions
are within acceptable limits.
Particulate
Nondegradation
Policy/3745-17-05
Degradation of air quality in any area where air quality is
better than required by 3745-17-02 Is prohibited.
Pertains to sites in certain locations
that may emit or allow the escape of
particulates (both stack and fugitive).
Consider for sites that will undergo
excavation, demolition, cap installation,
clearing and grubbing, and incineration.
ARAR
Air emissions may be involved as part of
the treatment in several of the
alternatives. Alternatives involving air
emissions will be coordinated with USEPA
and OEPA to ensure particulate emissions
are within acceptable limits.
Evaluation of
Wastes/3745-52-11
A-D
Any person generating a waste must determine if that
waste is a hazardous waste (either through listing or by
characteristic).
Pertains to sites at which wastes of
any type (both solid and hazardous) are
located.
ARAR
Any materials generated during
construction or implementation of remedial
actions will be evaluated to determine if
they are identifiable as a hazardous waste,
or if they are sufficiently similar to
hazardous wastes so that hazardous
waste management standards should be
applied.
Ground Water
Protection:
Applicability/
3745-54-90
Establishes circumstances under which an operator of a
hazardous waste facility must implement a groundwater
protection program or a corrective action program.
Pertains to all sites with land-based
hazardous waste units (surface
impoundments, waste piles, land
treatment units, and landfills), including
existing land-based areas of
contamination.
ARAR
Historic disposal of hazardous waste
occurred within OU 1. Groundwater
monitoring implemented as part of the
remedial alternatives will incorporate the
requirements of the hazardous waste
regulations.
Required Programs/
3745-54-91 (A)-(B)
Establishes requirements for conducting a groundwater
compliance monitoring and response program.
Whenever hazardous constituents from
a regulated unit are detected at the
compliance point, or whenever
groundwater protection standards are
exceeded between the compliance
point and the downgradient facility
property boundary.
ARAR
Exceedences of groundwater protection
standards have been observed within
OU 1. Groundwater monitoring program is
ongoing; a program will be implemented
as part of a remedial alternative that will
follow requirements of this ARAR.
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(•> 03
Table 1. (page 3 of 5)
Regulation Title or
Subject/Revised Code
Section and Pertinent
Paragraph
Regulation Description
Regulation Application
ARAR
Comments
Maximum Contaminant
Levels for Inorganic
Chemicals/3745-81-11
A.B
Presents maximum contaminant levels for inorganics.
Pertains to any site that has
contaminated surface or groundwater
that is either being used or has the
potential for being used as a drinking
water source.
ARAR
Because of the potential impacts to the
BVA, this standard will be applied.
Maximum Contaminant
Levels for Organic
Chemicals/3745-81-12
A.B.C
Presents maximum contaminant levels for organics.
Pertains to any site that has
contaminated surface or groundwater
that is either being used or has the
potential for being used as a drinking
water source.
ARAR
Because of the potential impacts to the
BVA, this standard will be applied.
Maximum Contaminant
Levels for Turbidity/
3745-81-13 A.B
Presents maximum contaminant levels for turbidity.
Pertains to any site that has
contaminated surface or groundwater
that is either being used or has the
potential for being used as a drinking
water source.
ARAR
Because of the potential impacts to the
BVA, this standard will be applied.
Maximum
Microbiological
Contaminant Levels/
3745-81-14 A-E
Presents maximum contaminant levels for microbiological
contaminants.
Pertains to any site that has
contaminated surface or groundwater
that is either being used or has the
potential for being used as a drinking
water source.
ARAR
Because of the potential impacts to the
BVA, this standard will be applied.
Maximum Contaminant
Levels for Radium-226,
-228, and Gross Alpha/
3745-81-15 A.B
Presents maximum contaminant levels for radium-226,
radium-228, and gross alpha particle activity.
Pertains to any site that has
contaminated surface or groundwater
that is either being used or has the
potential for being used as a drinking
water source.
ARAR
Because of the potential impacts to the
BVA, this standard will be applied.
Maximum Contaminant
Levels for Beta Particle
and Photon
Radioactivity/
3745-81-16 A.B
Presents maximum contaminant levels for beta particle and
photon radioactivity from man-made radionuclides.
Pertains to any site that has
contaminated surface or groundwater
that is either being used or has the
potential for being used as a drinking
water source.
ARAR
Because of the potential impacts to the
BVA, this standard will be applied.
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Table 1. (page 4 of 5)
Regulation Title or
Subject/Revised Code
Section and Pertinent
Paragraph
Regulation Description
Regulation Application
ARAR
Comments
Microbiological
Contaminant Sampling
and Analytical
Requirements/
3745-81-21 A-B
Presents sampling and analytical requirements for
microbiological contaminants.
Pertains to any site that has
contaminated surface or groundwater
that is either being used or has the
potential for being used as a drinking
water source.
ARAR
Appropriate methods for monitoring
compliance with ARARs will be
coordinated with OEPA and USEPA.
Turbidity Contaminant
Sampling and Analytical
Requirements/
3745-81-22 A-B
Presents sampling and analytical requirements for
turbidity.
Pertains to any site that has
contaminated surface or groundwater
that is either being used or has the
potential for being used as a drinking
water source.
ARAR
Appropriate methods for monitoring
compliance with ARARs will be
coordinated with OEPA and USEPA.
Inorganic Contaminant
Monitoring
Requirements/
3745-81-23 A-E
Presents monitoring requirements for inorganic
contaminants.
Pertains to any site that has
contaminated surface or groundwater
that is either being used or has the
potential for being used as a drinking
water source.
ARAR
Appropriate methods for monitoring
compliance with ARARs will be
coordinated with OEPA and USEPA.
Organic Contaminant
Monitoring
Requirements/
3745-81-24 A-E
Presents monitoring requirements for organic
contaminants.
Pertains to any site that has
contaminated surface or groundwater
that is either being used or has the
potential for being used as a drinking
water source.
ARAR
Appropriate methods for monitoring
compliance with ARARs will be
coordinated with OEPA and USEPA.
Analytical Methods for
Radioactivity/
3745 81-25 A-0
Presents analytical methods for radioactivity.
Pertains to any site that has
contaminated surface or groundwater
that is either being used or has the
potential for being used as a drinking
water source.
ARAR
Appropriate methods for monitoring
compliance with ARARs will be
coordinated with OEPA and USEPA.
Monitoring Frequency
for Radioactivity/
3745-81-26 A-C
Presents monitoring requirements for radioactivity.
Pertains to any site that has
contaminated surface or groundwater
that is either being used or has the
potential for being used as a drinking
water source.
ARAR
Appropriate methods for monitoring
compliance with ARARs will be
coordinated with OEPA and USEPA.
-------
o
O
o
o
S'
o'
3
Table 1. (page 5 of 5)
Regulation Title or
Subject/Revised Cod*
Section and Pertinent
Paragraph
Regulation Description
Regulation Application
ARAR
Comment!
Analytical Techniques/
3745-81-27 A-E
Presents general analytical techniques for maximum
contaminant levels.
Pertains to any site that has
contaminated surface or groundwater
that is either being used or has the
potential for being used as a drinking
water source.
ARAR
Appropriate methods for monitoring
compliance with ARARs will be
coordinated with OEPA and USEPA.
Requirements for a
Variance from MCLs/
3745-81-40 A-C
Provides criteria by which director may grant variance from
MCLs.
Pertains to any site which has
contaminanted ground or surface water
that is either being used, or has the
potential for use, as a drinking water
source.
ARAR
If required, the remedy will comply with
this provision.
Alternative Treatment
Technique Variance/
3745-81-46
Allows for the use of alternative treatment techniques to
attain MCLs.
Pertains to any site which has
contaminated ground or surface water
that is either being used, or has the
potential for use, as a drinking water
source.
ARAR
If required, the remedy will comply with
this provision.
Prohibition of
Nuisances/3767.14
Prohibition against throwing refuse, oil, or filth into lakes,
streams, or drains.
Pertains to all sites located adjacent to
lakes, streams, or drains.
ARAR
ARAR - applicable or relevant and appropriate requirement
BVA - Buried Valley aquifer
CERCLA - Comprehensive Environmental Response, Compensation, and Liability Act
MCL - maximum contaminant level
OEPA - Ohio Environmental Protection Agency
ORC ' Ohio Revised Code
OU 1 - Operable Unit 1
USEPA - U.S. Environmental Protection Agency
>
3
m ~
ui w
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Table 2. Federal Chemical-Specific ARARs for OU 1
Regulatory Program
Requirement
ARAR
Comment
CWA
Acute CWA freshwater toxicity
criterion (CWA S304).
Chronic CWA freshwater toxicity criterion (CWA
§304).
USEPA ambient water quality criteria for protection of
human health aquatic organisms, and drinking water
standards (CWA $304).
USEPA ambient water quality criteria for protection of
human health aquatic organisms only (CWA $304).
ARAR
Compliance is specifically
required by CERCLA $ 121(d)
where relevant and appropriate.
Will be applied except where
more appropriate standards exist.
For example, standards
specifically intended for
groundwater or drinking.
Safe Drinking Water Act
Maximum contaminant levels (40 CFR .11 to 141.16).
Maximum contaminant level goals (40 CFR $ 141.50)
ARAR
Compliance is specifically
required by CERCLA $ 121(d)
where relevant and appropriate.
Resource Conservation and Recovery
Act Groundwater Monitoring
Requirements
Groundwater Protection Program for Hazardous Waste
"Regulated Units" (40 CFR 264 Subpart F).
ARAR
Considered relevant and
appropriate because of historic
disposal of apparent hazardous
wastes.
ARAR - applicable or relevant and appropriate requirement
CERCLA - Comprehensive Environmental Response, Compensation, and Liability Act
CWA - Clean Water Act
USEPA - U.S. Environmental Protection Agency
-------
vl CO
Table 3. State Location-Specific ARARs for OU 1
Regulation Titla or
Subject/Revised Coda
Section and Pertinent
Paragraph
Regulation Description
Regulation Application
ARAR
Comments
"Digging" Where
Hazardous or Solid
Waste Facility Was
Located/3734.02 (H)
Filling, grading, excavating, building, drilling or mining on
land where a hazardous waste or solid waste facility was
operated is prohibited without prior authorization from the
director of the OEPA.
Pertains to any site where hazardous or
solid waste is located.
ARAR
Implementation of the substantive
provisions of state requirements relating
to intrusive activities at former disposal
sites as ARARs is required by Section
121(d) of CERCLA.
Prohibits Open
Dumping or Burning/
3734.03
Prohibits open burning or open dumping of solid waste or
treated or untreated infectious waste.
Pertains to any site at which solid
waste has come to be located or will
be generated during a rememdial
action.
ARAR
Solid wastes generated as part of the
remedy will be subject to this
requirement.
Hazardous Waste
Facility Environmental
Impact/3734.05
(D)(6)(c)
A hazardous waste facility installation and operation
permit shall not be approved unless the facility is proven
to represent the minimum adverse environmental impact
considering the state of available technology, the nature
and economics of various alternatives, and other pertinent
considerations.
Pertains to all sites where hazardous
wastes are located and/or where
hazardous wastes will be treated,
stored, or disposed of. May function
as siting criteria.
ARAR
While no permit is required, remedial
alternatives will be coordinated with the
USEPA and OEPA.
t
Hazardous Waste
Siting Criteria/
3734.05 (D)(6)(d)(g)|h)
(D)(6)(d). A hazardous waste facility installation and
operation permit shall not be approved unless it proves
that the facility represents the minimum risk of all of the
following:
(i) Contamination of ground and surface waters.
(ii) Fires or explosions from treatment, storage, or
disposal methods.
(iii) Accident during transportation.
(iv) Impact on public health and safety.
(v) Soil contamination.
(D)(6)(g)(h). Prohibits the following location for treatment,
storage and disposal of acute hazardous waste:
(i) Within 2,000 feet of any residence, school,
hospital, jail, or prison.
(ii) Any naturally occurring wetland.
(iii) Any flood hazard area.
(iv) Within any state park or national park or
recreation area.
Pertains to all sites at which hazardous
waste has come to be located and/or
at which hazardous will be treated,
stored, or disposed of. May function
as siting criteria.
ARAR
Water Use
Designations for
Southwest Ohio
Tributaries/ 3745-1-17
Establishes water use designations for stream segments
within the Southwest Ohio Tributaries Basin.
Pertinent if stream or stream segment
is onsite and is affected by site
conditions or if remedy includes direct
discharge. Used by DWQPA to
establish waste load allocations.
ARAR
Applicable to discharge.
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Table 3. (page 2 of 2)
Regulation Title or
Subject/Revised Code
Section and Pertinent
Paragraph
Regulation Description
Regulation Application
ARAR
Comments
Water Use
Designations for Great
Miami River/
3745-1-21
Establishes water use designations for stream segments
within the Great Miami River Basin.
Pertinent if stream or stream segment
is onsite and is affected by site
conditions or if remedy includes direct
discharge. Used by DWQPA to
establish waste load allocations.
ARAR
Applicable to discharge.
Location/Siting of New
GW Wells/3745-9-04
A,B
Mandates that groundwater wells be:
A) Located and maintained to prevent contaminants from
entering the well.
B) Located to be accessible for cleaning and
maintenance.
Pertains to all groundwater wells on
the site that either will be installed or
have been installed since February
1975. Would pertain during the FS if
new wells are constructed for
treatability studies.
ARAR
Wells installed as part of the remedy will
comply with this requirement.
Particulate
Nondegradation
Policy/3745-17-05
Degradation of air quality in any area where air quality is
better than required by 3745-17-02 is prohibited.
Pertains to sites in certain locations
that may emit or allow the escape of
particulates (both stack and fugitive).
Consider for sites that will undergo
excavation, demolition, cap installation,
clearing and grubbing, and incineration.
ARAR
Fugitive dust emission controls may be
required during construction. Alternatives
ipvolving air emissions will be coordinated
With USEPA and OEPA to ensure
particulate emissions are within
acceptable limits.
Open Burning
Standards in Restricted
Areas/3745-19-03 A-D
Open burning without prior authorization from OEPA is
prohibited.
Pertains to sites within a restricted area
(within the boundary of a municipality
and a zone extending beyond such
municipality).
ARAR
Disturbances Where
Hazardous or Solid
Waste Facility Was
Operated/
3745-27-13 C
Prohibits any filling, grading, excavating, building, drilling,
or mining on land where a hazardous waste facility or
solid waste facility was operated without prior
authorization from the director of the USEPA. Special
terms to conduct such activities may be imposed by the
director to protect the public and the environment.
Pertains to any site where hazardous or
solid waste has been managed, either
intentionally or otherwise. Does not
pertain to areas that have had one-time
leaks or spills.
ARAR
Implementation of the substantive
provisions of state requirements relating
to intrusive activities at former disposal
sites as ARARs is required by Section
121(d) of CERCLA.
ARAR - applicable or relevant and appropriate requirement
CERCLA - Comprehensive Environmental Response, Compensation, and Liability Act
DWQPA - Department of Water Quality Planning and Assessment
FS ¦ Feasibility Study
OEPA - Ohio Environmental Protection Agency
USEPA - U.S. Environmental Protection Agency
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Table 4. State Action-Specific ARARs for OU 1
Regulation Title or
Subject/Revised Coda
Section and Pertinent
Paragraph
Regulation Description
Regulation Application
ARAR
Comments
Prohibits Violation of
Air Pollution Control
Rules/3704.05 A-l
Prohibits emission of an air contaminant in violation of
Section 3704 or any rule, permit, order, or variance
issued pursuant to that section of the ORC.
May pertain to any site where air
contaminant emissions occur either as
a preexisting condition of the site or as
a result of remedial activities. Should
be considered for virtually all sites.
ARAR
Implementation of the substantive
provisions of state air requirements as
ARARs is required by Section 121(d) of
CERCLA.
"Digging" Where
Hazardous or Solid
Waste Facility Was
Located/3734.02 H
Filling, grading, excavating, building, drilling, or mining on
land where a hazardous waste or solid waste facility was
operated is prohibited without prior authorization from the
director of the OEPA.
Pertains to any site where hazardous
or solid waste is located.
ARAR
Implementation of the substantive
provisions of state requirements relating
to intrusive activities at former disposal
sites as ARARs is required by Section
121(d) of CERCLA.
Air Emissions from
Hazardous Waste
Facilities/3734.02 I
No hazardous waste facility shall emit any particulate
matter, dust, fumes, gas, mist, smoke, vapor, or odorous
substance that interferes with the comfortable enjoyment
of life or property or that is injurious to public health.
Pertains to any site where hazardous
waste will be managed so that air
emissions may occur. Consider for
sites that will undergo movement of
earth or incineration.
ARAR
Air emissions may be involved as part of
Hie treatment in several of the
alternatives. Alternatives involving air
emissions will be coordinated with
USEPA and OEPA to ensure emissions are
within acceptable limits.
Handling Low-Level
Radioactive Waste
Prohibited/
3734.02.7 A,B
A) Prohibits commingling low-level radioactive waste with
any type of solid, hazardous, or infectious waste.
B) No owner or operator of a solid, infectious, or
hazardous waste facility shall accept any radioactive
waste for transfer, storage, treatment, or disposal.
Pertains to all sites where low-level
radioactive waste is located.
ARAR
Radioactive wastes generated as part of
remedial actions at OU 1 will be managed
separately from non-radioactive materials.
Prohibits Open
Dumping or Burning/
3734.03
Prohibits open burning or open dumping of solid waste or
treated or untreated infectious waste.
Pertains to any site at which solid
waste has come to be located or will
be generated during a rememdial
action.
ARAR
Solid wastes generated as part of the
remedy will be subject to this
requirement.
Hazardous Waste
Facility Environmental
Impact/3734.05
(D)(6)(c)
A hazardous waste facility installation and operation
permit shall not be approved unless the facility is proven
to represent the minimum adverse environmental impact
considering the state of available technology, the nature
and economics of various alternatives, and other pertinent
considerations.
Pertains to all sites where hazardous
wastes are located and/or where
hazardous wastes wilt be treated,
stored, or disposed of. May function
as siting criteria.
ARAR
While no permit is required, remedial
alternatives will be coordinated with the
USEPA and OEPA.
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O 00
Table 4. (page 2 of 8)
Regulation Title or
Subject/Revised Cod*
Section and Pertinent
Paragraph
Regulation Description
Regulation Application
ARAR
Comments
Hazardous Waste
Siting Criteria/
3734.05 (D)(6)(d)(g)(h)
(D)(6)(d). A hazardous waste facility installation and
operation permit shall not be approved unless it proves
that the facility represents the minimum risk of all of the
following:
(i) Contamination of ground and surface waters.
(ii) Fires or explosions from treatment, storage, or
disposal methods.
(iii) Accident during transportation.
(iv) Impact on public health and safety.
(v) Soil contamination.
(D)(6)lg)(h). Prohibits the following location for
treatment, storage and disposal of acute hazardous
waste:
(i) Within 2,000 feet of any residence, school,
hospital, jail, or prison.
(ii) Any naturally occurring wetland.
(iii) Any flood hazard area.
(iv) Within any state park or national park or
recreation area.
Pertains to all sites at which hazardous
waste has come to be located and/or
at which hazardous will be treated,
stored, or disposed of. May function
as siting criteria.
ARAR
t
Conditions for Disposal
of Acute Hazardous
Waste/3734.14.1
Prohibits disposal of acute hazardous waste unless it:
(1) cannot be treated, recycled, or destroyed; (2) has
been reduced to its lowest level of toxicity; and (3) has
been completely encapsulated or protected to prevent
leaching.
Pertains to any site where acute
hazardous waste has come to be
located.
ARAR
Based on available information, only one
waste disposed of prior to construction of
the sanitary landfill, beryllium machining
wastes, may be determined to be an
acute hazardous waste. Currently, there
is some question whether such wastes
would have been considered off-
specification commercial chemical
products, identifiable as P015 listed acute
hazardous wastes. If such a listing is
appropriate, this standard will be
regarded as ARAR for any alternatives
involving generation of listed beryllium
hazardous wastes.
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-» CD
Table 4. (page 3 of 8)
Regulation Title or
Subject/Revised Code
Section and Pertinent
Paragraph
Regulation Description
Regulation Application
ARAR
Comment*
Analytical and
Collection
Procedures/3745-1-03
Specifies analytical methods and collection procedures for
surface water discharges.
Pertains both to discharges to surface
waters as a result of remediation and
to any onsite surface waters affected
by site conditions.
ARAR
Alternatives involving direct discharge will
comply.
Water Quality Criteria/
3745-1-07 C
Establishes water quality criteria for pollutants that do not
have specific numerical or narrative criteria identified in
Tables 7-1 through 7-15 of this rule.
Pertains both to discharges to surface
waters as a result of remedial action
and to any surface waters affected by
site conditions.
ARAR
Alternatives involving direct discharge will
comply.
Water Use
Designations for
Southwest Ohio
Tributaries/3745-1-17
Establishes water use designations for stream segments
within the Southwest Ohio Tributaries Basin.
Pertinent if stream or stream segment
is onsite and is affected by site
conditions or if remedy includes direct
discharge. Used by DWQPA to
establish waste load allocations.
ARAR
Applicable to discharge.
Water Use
Designations for Great
Miami River/3745-1-21
Establishes water use designations for stream segments
within the Great Miami River Basin.
Pertinent if stream or stream segment
is onsite and is affected by site
conditions or if remedy includes direct
discharge. Used by DWQPA to
establish waste load allocations.
ARAR
Alternatives involving direct discharge will
comply.
Location/Siting of New
GW Wells/
3745-9-04 A,B
Mandates that groundwater wells be:
A) Located and maintained to prevent contaminants from
entering the well.
B) Located to be accessible for cleaning and
maintenance.
Pertains to all groundwater wells on
the site that either will be installed or
have been installed since February
1975. Would pertain during the FS if
new wells are constructed for
treatability studies.
ARAR
Will be applied for new well installation as
part of any alternatives.
Construction of New
GW Wells/
3745-9-05 A1.B-H
Specifies minimum construction requirements for new
groundwater wells with regard to casing material, casing
depth, potable water, annular spaces, use of drive shoe,
openings to allow water entry, and contaminant entry.
Pertains to alt groundwater wells on
the site that either will be installed or
have been installed since 15 February
1975. Would pertain during the FS if
new wells are constructed for
treatability studies.
ARAR
Will be applied for new well installation as
part of any alternatives.
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KJ (D
Table 4. (page 4 of 8)
Regulation This or
Subject/Revised Code
Section and Pertinent
Paragraph
Regulation Description
Regulation Application
ARAR
Comment*
Casing Requirements
for New GW Wells/
3745-9-06 A,B,D,E
Establishes specific requirements for well casings, such as
suitable material, diameters, and conditions.
Pertains to all groundwater wells on
the site that either will be installed or
have been installed since 15 February
1975. Would pertain during the FS if
new wells are constructed for
treatability studies.
ARAR
Will be applied for new well installation as
part of any alternatives.
Surface Design of New
GW Wells/
3745-9-07 A-F
Establishes specific surface design requirements, such as
height above ground, well vents, and well pumps.
Pertains to all groundwater wells on
the site that either will be installed or
have been installed since 15 February
1975. Would pertain during the FS if
new wells are constructed for
treatability studies.
ARAR
Will be applied for new well installation as
part of any alternatives.
Start-up and Operation
of GW Wells/
3745-9-08 A,C
Requires disinfection of new wells and use of potable
water for priming pumps.
Pertains to all groundwater wells on
the site that either will be installed or
have been installed since 15 February
1975. Would pertain during the FS if
new wells are constructed for
treatability studies.
ARAR
t
Will be applied for new well installation as
part of any alternatives.
Maintenance and
Operation of GW
Wells/
3745-9-09 A-C,D1,E-G
Establishes specific maintenance and modification
requirements for casing, pump, and wells in general.
Pertains to all groundwater wells on
the site that either will be installed or
have been installed since 15 February
1975. Would pertain during the FS if
new wells are constructed for
treatability studies.
ARAR
Will be applied for new well installation as
part of any alternatives.
Abandonment of Test
Holes and GW Wells/
3745-9-10 A,B,C
Following completion of use, wells and test holes shall be
completely filled with grout or similar material and shall be
maintained in compliance of all regulations.
Pertains to all groundwater wells on
the site that either will be installed or
have been installed since 15 February
1975.
ARAR
Will be applied for new well installation as
part of any alternatives.
"De minimis" air
contaminant source
exemption/
3745-15-05
Provides that an air contaminant source is exempt from
permitting requirements, provided it has the potential to
emit no more than 10 pounds per day of criteria
pollutants or 1 ton per year of hazardous air pollutants.
Pertains to any site emitting air
pollutants.
ARAR
Will be applied to any remedy that has
the potential to emit criteria or hazardous
air pollutants.
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G> CD
Table 4. (page 5 of 8)
Regulation Title or
Subject/Revised Cod*
Section and Pertinent
Paragraph
Regulation Description
Regulation Application
ARAR
Comment*
Air Pollution Nuisances
Prohibited/
3745-15 07 A
Defines air pollution nuisance as the emission or escape
into the air (from any source) of smoke, ashes, dust, dirt,
grime, acids, fumes, gases, vapors, odors, and
combinations of the above that endanger health, safety,
or welfare of the public or cause personal injury or
property damage. Such nuisances are prohibited.
Pertains to any site that causes, or
may reasonably cause, air pollution
nuisances. Consider for sites that will
undergo excavation, demolition, cap
installation, methane production,
incineration, and waste fuel recovery.
ARAR
Air emissions may be involved as part of
the treatment in several of the
alternatives. Alternatives involving air
emissions will be coordinated with
USE PA and OEPA to ensure emissions are
within acceptable limits.
Emission Restrictions
for Fugitive Dust/
3745-17-08
A1 ,A2,8,D
All emissions of fugitive dust shall be controlled.
Pertains to sites that may have fugitive
emissions (non-stack) of dust.
Consider for sites that will undergo
grading, loading operations,
demolition, clearing and grubbing, and
construction.
ARAR
Air emissions may be involved as part of
the treatment in several of the
alternatives. Alternatives involving air
emissions will be coordinated with
USEPA and OEPA to ensure fugitive dust
emissions are within acceptable limits.
Open Burning
Standards in Restricted
Areas/3745-19-03 A-D
Open burning without prior authorization from OEPA is
prohibited.
Pertains to sites within a restricted
area (within the boundary of a
municipality and a zone extending
beyond such municipality).
ARAR
t
Ambient Air Quality
Standards and
Guidelines/
3745-21-02 A,B,C
Establishes specific air quality standards for carbon
monoxide, ozone and non-methane hydrocarbons.
Pertains to any site that will emit
carbon oxides, ozone, or non-methane
hydrocarbons. Consider for sites that
will undergo water treatment,
incineration, and fuel burning (waste
fuel recovery).
ARAR
Alternatives involving air emissions will
be coordinated with USEPA and OEPA to
ensure emissions are within acceptable
limits.
Methods of Ambient
Air Quality
Measurement/
3745-21-03 B,C,D
Specifies measurement methods to determine ambient air
quality for carbon monoxide, ozone, and non-methane
hydrocarbons.
Pertains to any site that will emit
carbon monoxide, ozone, or non-
methane hydrocarbons. Consider for
sites where treatment systems will
result in air emissions.
ARAR
Alternatives involving air emissions will
be coordinated with USEPA and OEPA to
ensure emissions are within acceptable
limits.
Non-degradation
Policy/3745-21-05
Prohibits significant and avoidable deterioration of air
quality.
Pertains to any site that will emit
carbon oxides and non-methane
hydrocarbons. Consider for sites that
will undergo water treatment,
incineration, and fuel burning (waste
fuel recovery).
ARAR
Alternatives involving air emissions will
be coordinated with USEPA and OEPA to
ensure emissions are within acceptable
limits.
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A CD
Table 4. (page 6 of 8)
Regulation Title or
Subject/Revised Cod*
Section and Pertinent
Peragraph
Regulation Description
Regulation Application
ARAR
Comment*
Organic Materials
Emission Control;
Stationary Sources/
3745-21-07 A,B,G,I,J
Requires control of emissions of organic materials from
stationary sources and best available technology.
Pertains to any site that is emitting or
will emit organic material. Consider for
sites that will undergo water
treatment, incineration, and fuel
burning (waste fuel recovery).
ARAR
Alternatives involving air emissions will
be coordinated with USEPA and OEPA to
ensure organic materials emissions are
within acceptable limits.
VOC Emissions
Control: Stationary
Sources/3745-21 -09
Establishes limitations for emissions of VOCs from
stationary sources.
Pertains to any site that is emitting or
will emit VOCs. Consider for sites that
will undergo water treatment.
ARAR
Alternatives involving air emissions will
be coordinated with USEPA and OEPA to
ensure VOC emissions are within
acceptable limits.
Exemptions to Solid
Waste Regulations/
3745-27-03 B
Defines exemptions to solid waste regulations and
establishes limitations on temporary storage of putrescible
waste or any solid waste that causes a nuisance or health
hazard. Storage of putrescible waste beyond 7 days is
considered open dumping.
Pertains to any site where solid waste
will be managed. Consider especially
for old landfills where solid waste may
be excavated and/or consolidated.
ARAR
Will be applied to any alternative that
involves generation of solid wastes.
t
Authorized, Limited
and Prohibited Solid
Waste Disposal/
3745-27-05 A,B,C
Establishes allowable methods of solid waste disposal:
sanitary landfill, incineration, composting. Prohibits
management by open burning and open dumping.
Pertains to any site where solid wastes
will be managed. Prohibits
management by open burning and
open dumping.
ARAR
Will be applied to any alternative that
involves generation of solid wastes.
None of the alternatives involve open
burning or open dumping.
Sanitary Landfill -
Ground Water
Monitoring/
3745-27-10 B-D
Groundwater monitoring program must be established for
all sanitary landfill facilities. The system must consist of
a sufficient number of wells that are located so that
samples indicate both upgradient (background) and
downgradient water samples. The system must be
designed per the minimum requirements specified in this
rule. The sampling and analysis procedures used must
comply with this rule.
Pertains to any new solid waste facility
and any expansions of existing solid
waste landfills onsite. Also may
pertain to existing areas of
contamination that are capped in-place
per the solid waste rules.
ARAR
Groundwater monitoring is contemplated
as an element of the remedy.
Disturbances Where
Hazardous or Solid
Waste Facility Was
Operated/
3745-27-13 C
Prohibits any filling, grading, excavating, building, drilling,
or mining on land where a hazardous waste facility or
solid waste facility was operated without prior
authorization from the director of the USEPA. Special
terms to conduct such activities may be imposed by the
director to protect the public and the environment.
Pertains to any site where hazardous
or solid waste has been managed,
either intentionally or otherwise. Does
not pertain to areas that have had one-
time leaks or spills.
ARAR
The RD/RA Work Plan will comply with
this requirement.
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tfi CD
Table 4. (page 7 of 8)
Regulation Title or
Subject/Revised Code
Section and Pertinent
Paragraph
Regulation Description
Regulation Application
ARAR
Comments
Post-Closure Care of
Sanitary Landfill
Facilities/
3745-27-14 A
Specifies the required post-closure care for solid waste
facilities. Includes continuing operation of leachate and
surface water management systems, maintenance of the
cap system, and groundwater monitoring.
Substantive requirements pertain to
newly created solid waste landfills
onsite, expansions of existing solid
waste landfills onsite, and existing
areas of contamination that are capped
per the solid waste rules.
ARAR
Evaluation of existing closed sanitary
landfill conditions will be included in all
but the no-action alternative and
necessary modifications/repairs will be
made.
Water/Air Permit
Criteria for Decision by
the Director/
3745-31-05
A permit to install or plans must demonstrate best
available technology and shall not interfere with or
prevent the attainment or maintenance of applicable
ambient air quality standards.
Pertains to any site that will discharge
to onsite surface water or will emit
contaminants into the air.
ARAR
Alternatives involving onsite water
discharge will comply. Air emissions may
be involved as part of the treatment in
several of the alternatives. Alternatives
involving air emissions will be coordinated
with USEPA and OEPA to ensure
^missions are within acceptable limits.
Evaluation of Wastes/
3745-52-11 A-D
Any person generating a waste must determine if that
waste is a hazardous waste (either through listing or by
characteristic).
Pertains to sites where wastes of any
type (both solid and hazardous) are
located.
ARAR
Any materials generated during
construction or implementation of
remedial actions will be evaluated to
determine if it is identifiable as a
hazardous waste, or if it is sufficiently
similar to a hazardous waste that
hazardous waste management standards
should be applied.
Prohibition of
Nuisances/3767.14
Prohibition against throwing refuse, oil, or filth into lakes,
streams, or drains.
Pertains to all sites located adjacent to
lakes, streams, or drains.
ARAR
Acts of Pollution
Prohibited/6111.04
Pollution of waters of the state is prohibited.
Pertains to any site that has
contaminated onsite surface water or
groundwater or will have a discharge
to onsite surface water or
groundwater.
ARAR
Implementation of the substantive
provisions of state water requirements as
ARARs is required by Section 121(d) of
CERCLA.
Rules Requiring
Compliance with
National Effluent Stds/
6111.04.2
Establishes regulations requiring compliance with national
effluent standards.
Pertains to any site that will have a
point source discharge.
ARAR
Alternatives involving onsite discharge
will comply.
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o
O
(9
o
55
o'
3
Table 4. (page 8 of 8)
Regulation Title or
Subject/Revised Code
Section and Pertinent
Paragraph
Regulation Description
Regulation Application
ARAR
Comment*
Water Pollution Control
Requirements-
Duty to
Comply/6111.07 A,C
Prohibits failure to comply with requirements of sections
6111.01 to 6111.08 or any rules, permit, or order issued
under those sections.
Pertains to any site that has
contaminated groundwater or surface
water or will have a discharge to
onsite surface or groundwater.
ARAR
implementation of the substantive
provisions of state water requirements as
ARARs is required by Section 121 (d) of
CERCLA.
OEPA Policy #DSW-
DERR 0100.027
National Pollution Discharge Elimination System:
Wastewater Discharges Resulting from Clean-up of
Response Action Sites Contaminated with VOCs.
Establishes guidelines for the disposal
of wastewaters, of both short- and
long-term discharge categories,
resulting from cleanup response action
sites contaminated with VOCs, and the
operating interface between the
involved OEPA divisions. For
discharges to surface water or storm
sewers, the Best Available Treatment
Technology/Best Available
Demonstrated Control Technology
(BATT/BADCT) must be applied to
achieve 5 /ig/L or less for each VOC
parameter listed.
TBC,
Not ARAR
This policy addresses short-term
discharges (pump tests and treatability
tests) and long-term discharges (interim
and remedial actions). This policy
provides guidelines for achievement of
less that 5 fig/L for specific VOC
parameters by utilizing BATT/BADCT for
those compounds. BATT/BADCT
Consists of air stripping, carbon columns,
or both or equivalent to achieve the 5
/ig/L or less.
ARAR - applicable or relevant and appropriate requirement
CERCLA - Comprehensive Environmental Response, Compensation, and liability Act
DWQPA - Department of Water Quality Planning and Assessment
FS - feasibility study
/jgIL - micrograms per liter
OEPA - Ohio Environmental Protection Agency
ORC - Ohio Revised Code
TBC - to be considered
USEPA - U.S. Environmental Protection Agency
VOC - volatile organic compound
>
3
3
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Table 5. Federal Action-Specific ARARs for OU 1
>
3
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00 w
Table 5. (page 2 of 3)
Action
Requirement
Prerequisite
Citation
ARAR
Comments
Discharge of
Treatment
System Effluent
Icont.)
Manaaement Reauirements:
Materials containing RCRA
hazardous wastes subject to
land disposal restrictions are
placed in another unit.
RCRA hazardous waste
placed at site after the
effective date of the
requirements.
40 CFR 122.41 (i)
40 CFR 136.1-136.4
40 CFR 122.41 (i)
40 CFR 268 (Subpart D)
See Closure in this exhibit.
/
Discharge must be monitored to
ensure compliance. Discharge will
monitor:
The mass of each pollutant.
The volume of effluent.
Frequency of discharge and
other measurements as
appropriate.
Approved test methods for waste
constituent to be monitored must be
followed. Detailed requirements for
analytical procedures and quality
controls are provided.
Comply with additional substantive
conditions such as:
Duty to mitigate any adverse
effects of any discharge.
Proper operation and
maintenance of treatment
systems.
Movement of excavated materials to
new location and placement in or on
land will trigger land disposal
restrictions for the excavated waste
or closure requirements for the unit in
which the waste is being placed.
The area from which materials are
excavated may require cleanup to
levels established by closure
requirements.
Discharge to
Storm Sewers
Requires storm water discharges to
be permitted under the federal (or
state) NPDES program. Different
requirements are applicable for
different classes and types of
discharges.
Protection of surface waters
against degradation resulting
from site discharges.
40 CFR 122
40 CFR 125
ARAR
Alternatives involving onsite
discharge to sewer systems
will comply.
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5 ? 3 Table 5. (page 3 of 31
*-?
Action
Requirement
Prerequisite
Citation
ARAR
Comments
Discharge of
Water into
Surface Water
Bodies
An NPDES permit is required for
discharging water offsite into surface
water bodies.
All surface water discharges must be
in compliance with promulgated Ohio
Stream Discharge Standards
Protection of surface waters
against degradation resulting
from site discharges.
40 CFR 122 and
40 CFR 125
ARAR
Alternatives involving onsite
discharge will comply.
ARAR - applicable or relevant and appropriate requirement
CWA - Clean Water Act
NPDES - National Pollutant Diacharge Elimination System
RCRA - Resource Conservation and Recovery Act
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ATTACHMENT C
COMMUNITY RELATIONS
ACTIVITIES FOR OU 1, AREA B
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MOUND
Operable Unit
1/a
rea B
Environmental
Restoration
Program
Ken Hacker, Manager
Addresses possible volatile
organic chemical contamina-
tion of the portion of the Buried
Valley Aquifer which underlies
the southwest corner of the
original Mound Plant.
OU1 covers four acres and
includes an historic landfill, the
site sanitary landfill and an
overflow pond.
The main concerns at this site
are volatile organic compounds
that may be migrating into the
groundwater. It is believed that
such contamination originates
from the historic landfill site that
was formerly used for open
burning and waste disposal.
September 1994
L
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PURPOSE
• Determine possible contamination ol the Buried Valley Aquifer from:
- historic landfill containing:
- Mound Plant used this area as burn area to dispose ol solid and liquid wastes
- Empty crushed thorium drums buried In this area in 1955 and 1956
- sanitary landfill
- Built in 1977 with materials excavated during construction ol overflow pond
• Constructed over site of encapsulated waste relocated from historic landfill
- overflow pond (stormwater retention pond)
• Gather enough information from this area to determine if a cleanup is necessary and, if so, how best to proceed with the
remedial action.
PRIMARY CONTAMINANTS OF CONCERN
*.,
Volatile organic compounds (VOCs)
WORK SCOPE
Determine by use of soil sampling, soil gas surveys and hydrogeology surveys, whether contaminants found in Area B are being
carried off-site through groundwater.
PROGRESS TO DATE
Subsurface soil sampling and soil gas sampling to identify contaminants in the soil, August-December, 1992
• Installation of 27 monitoring wells and piezometers. October-March, 1993
Aquifer pump test conducted using newly-installed and existing tesi wells to characterize groundwate* flow in the immediate
vicinity of Area B. May-June, 1993
• Fieldwork for RI/FS complete after aquifer pump test
DOCUMENTS IN PUBLIC REPOSITORY SCHEDULE FOR REMAINDER OF 1994
• History of Area B (February, 1991) * FSR/Proposed Plan to be complete in calendar year 1994
• Proposal for Additional Work (September, 1992) * Begin work on Record of Decision (ROD)
• Remedial!nvestigation Report(Rl) (July, 1994)
FUTURE SCHEDULE MILESTONES (Fully Funded)
FY95 • Prepare Feasibility Study/prepare Proposed Plan FY96: • Begin work on Remedial Design
• Complete FSR/PP
• Complele Record of Decision (ROD)
• Begin work on RD/RA Work Plan
For more information contact: EGSG Mound Community Relations at (513) 855-4143
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OU1 - Area B
Inclusion
In CERCLA
Program
1989
Remedial Investigation/
Feasibility Study
1 Assess Contamination
Determine Possible
Treatments
¦ Choose Best Treatments
You are here
9/2^94
RI/FS
Proposed Plan
(tq>on completion
of RI/FS)
U.S. EPA &
Ohio EPA
Comments
Public Comments
o
Record of
Decision
¦ Legal Document Spelling
Out Final Cleanup Plan
¦ Response to Public
Comments
• Explanation of Significant
Changes from Proposed
Plan
Cleanup
• Remedial Design
• Remedial Action
wsm
B
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MOUND
Environmental
Restoration
Program
Operable Unit 1/Area B
Ken Hacker, Manager
FACT SHEET
DOE Issues a Proposed Plan
Operable Unit 1 (OU1). Area B. of the Mound Plant occupies
approximately four acres In the southwestern portion ol the
plant site. This area of the plant is located over the eastern
side of the Burled Valley Aquifer (BVA) which has been desig-
nated as a sole source aquifer by the U.S. EPA. From 1948 to
1977. Mound used Area B, formerly a gravel excavation area,
for disposing of general trash and nonradioactive liquid
waste. Solid wastes, mostly paper, office and kitchen garbage,
were typically placed in a bum cage at Area B and Ignited to
reduce their volume; liquid wastes. Including solvents, oils,
and chemicals were typically dumped or burned. Much of this
waste was later relocated and encapsulated in a new site san-
itary landfill constructed in 1977. At that time, an overflow
pond for stormwater runoff was also constructed, partially
covering the historic landfill site. After 1977, waste was no
longer disposed of in Area B. Now, testing has revealed that
the volatile organic compounds (VOCs) from the Area B
historic landfill nave migrated through soils and groundwater
into a portion of the Buried Valley aouifer beneath the land-
fill. In addition, tritium was detected in past water samples
taken from wells in Area B. although the concentration was
below the drinking water maximum contaminant level.
Mound studies have shown the source of tritium In the BVA
to be contaminated sediments in the Miami-Erie Canal. Thus,
the environmental concerns in Area B center on VOCs in the
contaminated soils and waste materials contained within the
area and on the groundwater system directly beneath and ad-
jacent to the Mound site. The contaminated groundwater in
OU1 Is a concern at the site because of the potential for
directly Ingesting contaminants through drinking water and
the possible onsite migration of the VOC-contaminated
portion of the aquifer.
November 1994
Remedial Investigation and Feasibility Study Completed
To address VOC soil and water contamination concerns In Area B, a baseline risk assessment was done,
followed by a remedial investigation and feasibility study (RI/FS). The baseline risk assessment was
structured to address future public health risks, assuming no remedial actions were undertaken. The study
focused on exposure of hypothetical future residents and site workers to soil and groundwater
contamination through inhalation, incidental Ingestion, external exposure to radiation emitted from
radionuclides In the soil, and skin contact with the soli. Ingestion and inhalation contribute almost all of
the risk, and groundwater Is the most important exposure medium. Because groundwater would contribute
most of the carcinogenic and noncarclnogenlc risks to future residents or workers, it is the focus of the
remedial efforts to reduce the overall risk.
The (Rl/FS) examined seven alternatives for protecting human health and the environment while achieving
the remedial goals. All seven of the alternatives include several common components. Each alternative
includes surface controls, such as grading and lining existing ditches to manage runon and runoff;
institutional controls, such as fencing and access restrictions to limit access to the site; and long-term
groundwater monitoring. Each of the alternatives Is discussed in the "Operable Unit 1 Proposed Plan." This
and other documents on OU1 are available to the public in the CERCLA Reading Room at the Mlamlsburg
Senior Adult Center.
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fn
WHAT ARE VOLATILE
ORGANIC COMPOUNDS?
Readers of Superfund Update may
recall the feature article on volatile
organic compounds (VOCs) in the
January/February 1994 issue. VOCs
comprise a wide array of everyday
chemicals. From gasoHne, anti-
freeze, and pesticide sprays, to
paints, glues, and waxes-VOCs are
found in household and industrial
roducts all around us. Though
ndispensabie to modern fife, VOCs
can pose some significant hazards.
And because they are sc common,
they often turn up as contaminants in
the environment. VOCs evaporate
readily and so can quickly fill an en-
closed space with noxious and dang-
erous fumes. They do not dissolve
easily In water and so pose water
contamination problems when they
find their way to lakes, rivers, and
streams. Long-term exposure to low
concentrations can affect the liver,
kidneys, hean, blood, reproductive
organs, and nervous system. Some
VOCs, such as benzene, are known
to cause cancer. VOCs are released
into the environment through evapor-
ation, accidental spills, leaks, or
inadequate disposal methods. Drink-
Ing VOC-contaminaled water, inhal-
ing evaporated VOCs, or absorbing
VOCs through skip contact are the
main exposure routes for humans.
¦The CEflCLA statute currently con-
siders 33 VOCs to bB hazardous
substances that may pose a poten-
tial hazard to human health or the
environment if improperly treated, -
stored, transported, or disposed. At
Mound, VOCs have been used in the
past to clean or degrease metal
parts/tools, molds, and other equip-
ment, Among those In common use
were acetone, benzene, chloroform,
freon, and toluene.
if VOCs are discovered in soil or
water in concentrations above fed-
eral or state standards, environ-
mental laws such as CERCLA re-
quire cleanup action: There are a
number of remedies for handling •
VOC - contamination in soil and
groundwater. Contaminated soils
can be covered with caps to elim-
inate potential exposure routes; ;
excavated soil may be transported to
a landfill or incinerator for disposal;
soils may be treated m place by soil
vapor extraction; VOC-contaminated;i;
groundwater may be pumped out for
treatment and discharge.
The Preferred Alternative
The preferred alternative for cleaning up the VOC-contaminated soils
and groundwater at OU1 combines collection, treatment, and disposal.
Because this alternative reduces the toxicity and volume of contami-
nated water and controls its migration, it Is protective of both the
Mound Plant well field and the Burled Valley aquifer. The action would
effectively capture contaminated groundwater beneath the Operable
Unit 1 site for treatment before It migrates offsite. Treatment methods
for VOCs then could include ultraviolet (UV) oxidation treatment, cas-
cade aeration, or conventional air stripping. A final selection of treat-
ment technologies will be done following the public comment period
during the remedial design phase. Based on current information, the
DOE, in consultation with the U.S. and Ohio Environmental Protection
Agencies, will select a final remedy for the site after the public comment
period has ended and the information submitted during this time will
nave been reviewed and considered.
-th Star
Soil Sampling at Operable Unit 1
PUBLIC COMMENT PERIOD
Beginning November 15, 1994, and continuing through December 30,
1994, the Department of Energy is accepting public comments on the
Proposed Plan for Operable Unit 1.
The public is invited, and encouraged to review the Proposed Plan, at
the CERCLA Public Reading Room, Mlamisburg Senior Adult Center,
305 Central Avenue, Miamisburg, Ohio.
Comments can be sent In writing to:
Jolene Walker
EG&G Mound Community Relations
P.O. Box 3000, OSE-245
Miamisburg, Ohio 45343-3000
The public can also give comments at a public hearing for OU1 on
Thursday. December 8. 1994, at 7:00 p.m. in the Miamisburg Civic
Center Council Chambers, 10 N. First Street, Miamisburg, Onlo.
For more information, contact: EG&G Mound Community Relators al (513) 865-4140.
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MOUND
Environmental
Restoration
Program
Operable Unit 1/Area B
Ken Hacker, Manager
FACT SHEET #2
December 1994
Proposed Plan Supplementary Information
Based on official Public Comments received
at the December 8, 1994. Public Meeting for
Operable Unit 1 Proposed Plan, a question
was raised concerning Table 1 on page 9 of
the Proposed Plan. The question concerned
the apparent similarity of Alternatives 3 and
4 with the exception of maximum total cost.
The attachment clarifies Table 1 by sum-
marizing the reduction of toxicity, mobility or
volume of contaminants that each Alter-
native addresses.
Alternative 3 meets the mobility and volume
reduction statutory preference for selecting
remedial actions (page 4-10 of the Operable
Unit 1 Feasibility Study). It does not address
toxicity reduction, which is also a statutory
preference for selecting remedial actions.
Therefore, DOE In consultation with U.S.
EPA and Ohio EPA, has determined that
Alternative 4, which includes treatment to
reduce toxicity, is preferable. The reduction
of toxicity, mobility or volume for Alternative
4 is explained on page 4-14 of the Operable
Unit 1 Feasibility Study.
Guidance from the Ohio Environmental Pro-
tection Agency states that waste water
discharges resulting from cleanup of res-
ponse action sites contaminated with volatile
organic compounds (VOCs) need to be
treated with best available technology for
toxicity reduciton. The State of Ohio believes
that Alternative 3 does not meet those re-
quirements.
Table 1 identifies the 7 primary evaluation
criteria required by 40 CFR 300. This law
also gives 2 additional "modifying criteria"
which are (1) state acceptance and (2) com-
munity acceptance. Based on the States
position on Alternative 3, Alternative 4 was
chosen as the preferred alternative. The final
decision will also Include evaluation of com-
munity acceptance based on public com-
ments received.
Alternatives 3 through 9 comply with ARARs
and achieve adequate protection of human
health and the environment. These alterna-
tives are correctly identified in Table 1 of the
Proposed Plan, however, the text on page 8
of the Proposed Plan incorrectly stated that
all alternatives met ARARs.
Please keep in mind that the Proposed Plan
only identifies the preferred option for clean-
up of contamination of Operable Unit 1. A
more detailed description of the alternatives
is provided in the Operable Unit 1 Feasibility
Study.
Public Comment Period
The public comment period for the Proposed Plan has been extended to January 31, 1995. The
public is invited, and encouraged, to review the Proposed Plan, Feasibility Study, and
Supplementary Information, at the DOE Public Reading Room, Miamisburg Senior Adult
Center, 305 Central Ave., Miamisburg, Ohio. For questions or comments, contact EG&G
Community Relations at (513) 865-4140.
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Table 1. Summary of Remedial Action Alternative Comparison
Ahematlva
Short Title
Complies
With
ARARs
Short-term
Effectiveness
Long-term
Effectiveness
Protects
Human
Health end
the
Environment
Reduces
TMV
Implementebllity
Total Cost
1
No Action
No
No
No
No
No
Easy
$0
2
Institutional
No
No
No
No
No
Easy
$3,980,000
3
Collect/
Disposal
Yes
Adequate*
Yes
Adequate
Yes
MV
Less Difficult
$262,000°
4
Collect/Treat/
Disposal
Yes
Adequate*
Yes
Adequate
Yes
TMV
Less Difficult
$1,740,000°
5
Collect/Treat/
Disposal/Cap
Yes
Adequate"
Yes
Adequate
Yes
TMV
Less Difficult
$2,390,000°
6
Contain/Collect/
Treat/Disposal
Yes
Adequate"
Yes
Adequate
Yes«
TMV
Moderately
Difficult
$2,650,000°
7
Contain/Collect/
Treat/Disposal/
Cap
Yes
Adequate"
Yes
Adequate
Yes
TMV
Moderately
Difficult
$3,300,000°
8
In-situ GW
Treatment
Yes
Adequate"
Yes
Adequate
Yes
TMV
More Difficult
$1,980,000°
9
In-situ GW
Treatment/Cap
Yes
Adequate"
Yes
Adequate
Yes
TMV
More Difficult
$2,630,000°
•Quicker implementation when compared to other alternatives.
"Longer construction time when compared to other alternatives.
This Total Cost is in addition to the Total Cost shown for Alternative 2 (common cost).
ARARs - Applicable or relevant and appropriate requirements.
TMV - Toxicity, Mobility, or Volume.
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